000
FXUS63 KILX 201555
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
955 AM CST TUE JAN 20 2009
.DISCUSSION...
ISSUED 955 AM CST TUE JAN 20 2009
MORNING SURFACE ANALYSIS SHOWS RIDGE OF HIGH PRESSURE OVER THE
ROCKIES/WESTERN PLAINS...WITH COLD NORTHERLY FLOW CONTINUING
ACROSS CENTRAL ILLINOIS. SKIES ARE SUNNY...EXCEPT FOR SOME
LAKE-ENHANCED CLOUDS STRETCHING FROM KANKAKEE SOUTHWESTWARD INTO
THE BLOOMINGTON AND CHAMPAIGN AREAS. A FEW SNOW FLURRIES HAVE BEEN
REPORTED FROM TIME TO TIME UNDER THIS CLOUD BAND...HOWEVER THE
MORE SIGNIFICANT SNOW-SHOWERS WILL REMAIN FURTHER N/NE ACROSS
NORTHWEST INDIANA. CU-RULE SUGGESTS STEEP ENOUGH LAPSE RATES TO
TRIGGER SCT DIURNAL CU AS THE DAY GOES ON...SO THE CURRENT MOSTLY
SUNNY FORECAST LOOKS JUST FINE. TEMP TRENDS APPEAR TO BE MOSTLY ON
TRACK AS WELL...ALTHOUGH HAVE LOWERED AFTERNOON HIGHS BY A COUPLE
OF DEGREES DUE TO COLDER THAN FORECAST EARLY MORNING LOWS AND
CONTINUED NORTHERLY FLOW THROUGHOUT THE DAY. HIGHS WILL RANGE FROM
THE UPPER TEENS ALONG AND NORTH OF I-74...TO THE MIDDLE 20S SOUTH
OF I-70. CHANGES TO FORECAST ARE MINOR...SO NO ZONE UPDATE IS
NEEDED AT THIS TIME.
BARNES
&&
.AVIATION...
ISSUED 547 AM CST TUE JAN 20 2009
QUIET/VFR CONDITIONS EXPECTED ACROSS THE CENTRAL ILLINOIS
TERMINALS THROUGH THE 12Z TAF PERIOD FOR THE MOST PART. ONE SMALL
CAVEAT TO THIS EXPECTATION IS A SMALL PATCH OF MVFR LEVEL CLOUDS
AND ASSOCIATED LIGHT SNOW THAT HAS BROKEN OFF THE MAIN LAKE EFFECT
BAND DOWN THE SPINE OF LAKE MICHIGAN. DO NOT EXPECT THESE
CLOUDS/SNOWS TO BE A MAJOR PLAYER TODAY AS THEY MOVE FURTHER FROM
THE LAKE AND DISSIPATE...THOUGH THEY WILL LIKELY IMPACT KBMI FOR A
FEW HOURS THIS MORNING. THE THREAT FOR ADDITIONAL LAKE CLOUDS/SNOW
WILL CONTINUE TO DIMINISH AS THE LOW LEVEL FLOW TURNS MORE
NORTHWESTERLY.
OTHERWISE...HIGH PRESSURE WILL GRADUALLY BUILD ACROSS THE
TERMINALS THROUGH THE PERIOD. WINDS...GENERALLY AOB 10 KTS...WILL
BACK FROM NORTHWEST TO SOUTHWEST BY LATER TONIGHT AS THE RIDGE
AXIS SLIDES BY. VFR MID/HIGH CLOUD CEILINGS ARE EXPECTED TO
DEVELOP TONIGHT AS RETURN FLOW DEVELOPS ON THE BACK SIDE OF THE
RIDGE.
BAK
&&
.PREV DISCUSSION...
ISSUED 257 AM CST TUE JAN 20 2009
SHORTWAVE BROUGHT A ROUND OF PRECIP LATE LAST NIGHT AND INTO THE
EARLY HOURS THIS MORNING WITH A DUSTING OF SNOW. ALTHOUGH
ADDITIONAL SHORTWAVES ARE PROGGED IN THE MODELS TO MISS THE
FA...THE PATTERN SHIFT IS POORLY REPRESENTED IN THE MODELS UP TO
THIS POINT AND LITTLE CONFIDENCE IN THE DRY FORECAST AS LONG AS
THE FLOW REMAINS N/NWRLY. FORECAST IS IN A PRECARIOUS POSITION
BETWEEN SOLUTIONS...AND RATHER CONSERVATIVE THROUGH THE MED RANGE.
NAM STILL PREFERRED IN THE SHORTER TERM...HOWEVER...DISCREPANCIES
WITH THE PATTERN SHIFT GOING INTO THE WEEKEND BTWN THE GFS AND THE
ECMWF ARE BLENDED WITH THE 00Z ISSUANCES. AS A RESULT...LITTLE IN
THE WAY OF CHANGES FOR THE FORECAST OVERALL. MAJOR ISSUES ARE THE TEMPS
THURSDAY NIGHT...THE FROPA ON FRI EARLY...AND THE SHIFT IN THE
WAVE PATTERN OVER THE CONUS INTO THE WEEKEND. TELECONNECTIONS ARE
AND HAVE BEEN HINTING AT A PATTERN SHIFT THAT HAS BEEN MIRRORED IN
THE RETURN TO A MORE ZONAL FLOW IN THE OPERATIONAL MODELS. PROBLEM
IS THAT THE SHIFT IS NOT HAPPENING...AND THE OSCILLATION FORECASTS
BASED ON ENSEMBLES ARE LOOKING MORE AND MORE DRASTIC...AND
UNLIKELY TO MAKE SUCH A VIOLENT SHIFT. THIS IS MORE OF A GLITCH IN
THE MED RANGE UNTIL THE MODELS QUIT STUMBLING OVER THE FIRST GUESS
BIAS.
SHORT TERM...TODAY AND TOMORROW...
A BRIEF BREAK FROM THE PRECIP EXPECTED FOR TODAY...HIGHS IN THE
20S AS THE NWRLY FLOW CONTINUES. POORLY SAMPLED NWRN CANADA AND
MASKING BANK OF CLOUDS AT THE TOP OF THE RIDGE ON WV MAY BE HIDING
EMBEDDED SHORTWAVES THAT MAY BRING FLURRIES OVER THE FA IN THE
SHORT TERM...BUT FOR NOW WILL KEEP THE FORECAST WITHOUT PRECIP
MENTION. TOMORROW SOUTHERLY FLOW SETS UP...USHERING IN SOME WARMER
TEMPS AT THE SFC...AND MELTING SOME OF THE SNOWPACK OVER THE CWA.
LONG TERM...THURSDAY THROUGH SATURDAY...
SLOW WARM UP CONTINUES THROUGH THURSDAY...THOUGH TRUNCATED BY THE
PASSAGE OF A FRONT WITH SOME RATHER COLD AIR BEHIND IT EARLY
MORNING FRIDAY. TIMING OF THE FRONT IS SHIFTING LATER...ENOUGH TO
ALTER THE MIN TEMPS THU NIGHT/FRI MORNING. BUT SLOWING THE
PROGRESSION OF THE SFC SYSTEM IS ALSO IN DIRECT OPPOSITION TO THE
ATTEMPT OF THE MODELS TO PUSH A MORE ZONAL FLOW INTO THE WEEKEND
OVER THE ERN HALF OF THE CONUS.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 201147
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
547 AM CST TUE JAN 20 2009
.DISCUSSION...
ISSUED 257 AM CST TUE JAN 20 2009
SHORTWAVE BROUGHT A ROUND OF PRECIP LATE LAST NIGHT AND INTO THE
EARLY HOURS THIS MORNING WITH A DUSTING OF SNOW. ALTHOUGH
ADDITIONAL SHORTWAVES ARE PROGGED IN THE MODELS TO MISS THE
FA...THE PATTERN SHIFT IS POORLY REPRESENTED IN THE MODELS UP TO
THIS POINT AND LITTLE CONFIDENCE IN THE DRY FORECAST AS LONG AS
THE FLOW REMAINS N/NWRLY. FORECAST IS IN A PRECARIOUS POSITION
BETWEEN SOLUTIONS...AND RATHER CONSERVATIVE THROUGH THE MED RANGE.
NAM STILL PREFERRED IN THE SHORTER TERM...HOWEVER...DISCREPANCIES
WITH THE PATTERN SHIFT GOING INTO THE WEEKEND BTWN THE GFS AND THE
ECMWF ARE BLENDED WITH THE 00Z ISSUANCES. AS A RESULT...LITTLE IN
THE WAY OF CHANGES FOR THE FORECAST OVERALL. MAJOR ISSUES ARE THE TEMPS
THURSDAY NIGHT...THE FROPA ON FRI EARLY...AND THE SHIFT IN THE
WAVE PATTERN OVER THE CONUS INTO THE WEEKEND. TELECONNECTIONS ARE
AND HAVE BEEN HINTING AT A PATTERN SHIFT THAT HAS BEEN MIRRORED IN
THE RETURN TO A MORE ZONAL FLOW IN THE OPERATIONAL MODELS. PROBLEM
IS THAT THE SHIFT IS NOT HAPPENING...AND THE OSCILLATION FORECASTS
BASED ON ENSEMBLES ARE LOOKING MORE AND MORE DRASTIC...AND
UNLIKELY TO MAKE SUCH A VIOLENT SHIFT. THIS IS MORE OF A GLITCH IN
THE MED RANGE UNTIL THE MODELS QUIT STUMBLING OVER THE FIRST GUESS
BIAS.
SHORT TERM...TODAY AND TOMORROW...
A BRIEF BREAK FROM THE PRECIP EXPECTED FOR TODAY...HIGHS IN THE
20S AS THE NWRLY FLOW CONTINUES. POORLY SAMPLED NWRN CANADA AND
MASKING BANK OF CLOUDS AT THE TOP OF THE RIDGE ON WV MAY BE HIDING
EMBEDDED SHORTWAVES THAT MAY BRING FLURRIES OVER THE FA IN THE
SHORT TERM...BUT FOR NOW WILL KEEP THE FORECAST WITHOUT PRECIP
MENTION. TOMORROW SOUTHERLY FLOW SETS UP...USHERING IN SOME WARMER
TEMPS AT THE SFC...AND MELTING SOME OF THE SNOWPACK OVER THE CWA.
LONG TERM...THURSDAY THROUGH SATURDAY...
SLOW WARM UP CONTINUES THROUGH THURSDAY...THOUGH TRUNCATED BY THE
PASSAGE OF A FRONT WITH SOME RATHER COLD AIR BEHIND IT EARLY
MORNING FRIDAY. TIMING OF THE FRONT IS SHIFTING LATER...ENOUGH TO
ALTER THE MIN TEMPS THU NIGHT/FRI MORNING. BUT SLOWING THE
PROGRESSION OF THE SFC SYSTEM IS ALSO IN DIRECT OPPOSITION TO THE
ATTEMPT OF THE MODELS TO PUSH A MORE ZONAL FLOW INTO THE WEEKEND
OVER THE ERN HALF OF THE CONUS.
HJS
&&
.AVIATION...
ISSUED 547 AM CST TUE JAN 20 2009
QUIET/VFR CONDITIONS EXPECTED ACROSS THE CENTRAL ILLINOIS
TERMINALS THROUGH THE 12Z TAF PERIOD FOR THE MOST PART. ONE SMALL
CAVEAT TO THIS EXPECTATION IS A SMALL PATCH OF MVFR LEVEL CLOUDS
AND ASSOCIATED LIGHT SNOW THAT HAS BROKEN OFF THE MAIN LAKE EFFECT
BAND DOWN THE SPINE OF LAKE MICHIGAN. DO NOT EXPECT THESE
CLOUDS/SNOWS TO BE A MAJOR PLAYER TODAY AS THEY MOVE FURTHER FROM
THE LAKE AND DISSIPATE...THOUGH THEY WILL LIKELY IMPACT KBMI FOR A
FEW HOURS THIS MORNING. THE THREAT FOR ADDITIONAL LAKE CLOUDS/SNOW
WILL CONTINUE TO DIMINISH AS THE LOW LEVEL FLOW TURNS MORE
NORTHWESTERLY.
OTHERWISE...HIGH PRESSURE WILL GRADUALLY BUILD ACROSS THE
TERMINALS THROUGH THE PERIOD. WINDS...GENERALLY AOB 10 KTS...WILL
BACK FROM NORTHWEST TO SOUTHWEST BY LATER TONIGHT AS THE RIDGE
AXIS SLIDES BY. VFR MID/HIGH CLOUD CEILINGS ARE EXPECTED TO
DEVELOP TONIGHT AS RETURN FLOW DEVELOPS ON THE BACK SIDE OF THE
RIDGE.
BAK
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 200929 CCA
AFDILX
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE LINCOLN IL
328 AM CST TUE JAN 20 2009
.DISCUSSION...
ISSUED 257 AM CST TUE JAN 20 2009
SHORTWAVE BROUGHT A ROUND OF PRECIP LATE LAST NIGHT AND INTO THE
EARLY HOURS THIS MORNING WITH A DUSTING OF SNOW. ALTHOUGH
ADDITIONAL SHORTWAVES ARE PROGGED IN THE MODELS TO MISS THE
FA...THE PATTERN SHIFT IS POORLY REPRESENTED IN THE MODELS UP TO
THIS POINT AND LITTLE CONFIDENCE IN THE DRY FORECAST AS LONG AS
THE FLOW REMAINS N/NWRLY. FORECAST IS IN A PRECARIOUS POSITION
BETWEEN SOLUTIONS...AND RATHER CONSERVATIVE THROUGH THE MED RANGE.
NAM STILL PREFERRED IN THE SHORTER TERM...HOWEVER...DISCREPANCIES
WITH THE PATTERN SHIFT GOING INTO THE WEEKEND BTWN THE GFS AND THE
ECMWF ARE BLENDED WITH THE 00Z ISSUANCES. AS A RESULT...LITTLE IN
THE WAY OF CHANGES FOR THE FORECAST OVERALL. MAJOR ISSUES ARE THE TEMPS
THURSDAY NIGHT...THE FROPA ON FRI EARLY...AND THE SHIFT IN THE
WAVE PATTERN OVER THE CONUS INTO THE WEEKEND. TELECONNECTIONS ARE
AND HAVE BEEN HINTING AT A PATTERN SHIFT THAT HAS BEEN MIRRORED IN
THE RETURN TO A MORE ZONAL FLOW IN THE OPERATIONAL MODELS. PROBLEM
IS THAT THE SHIFT IS NOT HAPPENING...AND THE OSCILLATION FORECASTS
BASED ON ENSEMBLES ARE LOOKING MORE AND MORE DRASTIC...AND
UNLIKELY TO MAKE SUCH A VIOLENT SHIFT. THIS IS MORE OF A GLITCH IN
THE MED RANGE UNTIL THE MODELS QUIT STUMBLING OVER THE FIRST GUESS
BIAS.
SHORT TERM...TODAY AND TOMORROW...
A BRIEF BREAK FROM THE PRECIP EXPECTED FOR TODAY...HIGHS IN THE
20S AS THE NWRLY FLOW CONTINUES. POORLY SAMPLED NWRN CANADA AND
MASKING BANK OF CLOUDS AT THE TOP OF THE RIDGE ON WV MAY BE HIDING
EMBEDDED SHORTWAVES THAT MAY BRING FLURRIES OVER THE FA IN THE
SHORT TERM...BUT FOR NOW WILL KEEP THE FORECAST WITHOUT PRECIP
MENTION. TOMORROW SOUTHERLY FLOW SETS UP...USHERING IN SOME WARMER
TEMPS AT THE SFC...AND MELTING SOME OF THE SNOWPACK OVER THE CWA.
LONG TERM...THURSDAY THROUGH SATURDAY...
SLOW WARM UP CONTINUES THROUGH THURSDAY...THOUGH TRUNCATED BY THE
PASSAGE OF A FRONT WITH SOME RATHER COLD AIR BEHIND IT EARLY
MORNING FRIDAY. TIMING OF THE FRONT IS SHIFTING LATER...ENOUGH TO
ALTER THE MIN TEMPS THU NIGHT/FRI MORNING. BUT SLOWING THE
PROGRESSION OF THE SFC SYSTEM IS ALSO IN DIRECT OPPOSITION TO THE
ATTEMPT OF THE MODELS TO PUSH A MORE ZONAL FLOW INTO THE WEEKEND
OVER THE ERN HALF OF THE CONUS.
HJS
&&
.AVIATION...
ISSUED 1137 PM CST MON JAN 19 2009...FOR THE 06Z TAFS
SNOW SHOWERS ARE QUICKLY COMING TO AN END ACROSS CENTRAL
ILLINOIS...AS THE UPPER SHORTWAVE DROPS SOUTH OF THE CWA. FLURRIES
AND MVFR CIGS SHOULD PREVAIL THE REST OF THE NIGHT. SATELLITE
IMAGES ARE SHOWING BREAKS IN THE CLOUD COVER ACROSS S WIS AND N
IL. WENT WITH SOME VFR CIGS TO SHOW THAT TREND...BUT KEPT A
CEILING AT ALL SITES. PIA/BMI/CMI WILL HAVE THE BEST CHANCE AT
CLEARING SKIES BEFORE SUNRISE. GUID IS INDICATING MVFR CIGS THE
REST OF THE NIGHT...AND SPORADIC OBSERVATIONS UPSTREAM WOULD
SUPPORT THAT AS WELL.
WILL HOLD OFF ON WIDESPREAD CLEARING IN THE TAFS UNTIL MID DAY OR
AFTERNOON.
ANOTHER DISTURBANCE IS INDICATED IN THE 00Z MODELS THAT MAY AFFECT
THE EASTERN CWA...POSSIBLY CMI...WITH SOME SNOW TUES. WILL NOT
JUMP ON THAT JUST YET...AND KEEP THINGS VFR WITH NO CIG IN THE AFTERNOON.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 200927
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
327 AM CST TUE JAN 20 2009
.DISCUSSION...
ISSUED 257 AM CST TUE JAN 20 2009
SHORTWAVE BROUGHT A ROUND OF PRECIP LATE LAST NIGHT AND INTO THE
EARLY HOURS THIS MORNING WITH A DUSTING OF SNOW. ALTHOUGH
ADDITIONAL SHORTWAVES ARE PROGGED IN THE MODELS TO MISS THE
FA...THE PATTERN SHIFT IS POORLY REPRESENTED IN THE MODELS UP TO
THIS POINT AND LITTLE CONFIDENCE IS THE DRY FORECAST AS LONG AS
THE FLOW REMAINS N/NWRLY. FORECAST IS IN A PRECARIOUS POSITION
BETWEEN SOLUTIONS...AND RATHER CONSERVATIVE THROUGH THE MED RANGE.
NAM STILL PREFERRED IN THE SHORTER TERM...HOWEVER...DISCREPANCIES
WITH THE PATTERN SHIFT GOING INTO THE WEEKEND BTWN THE GFS AND THE
ECMWF ARE BLENDED WITH THE 00Z ISSUANCES. AS A RESULT...LITTLE IN
THE WAY OF CHANGES FOR THE FORECAST OVERALL. MAJOR ISSUES ARE THE TEMPS
THURSDAY NIGHT...THE FROPA ON FRI EARLY...AND THE SHIFT IN THE
WAVE PATTERN OVER THE CONUS INTO THE WEEKEND. TELECONNECTIONS ARE
AND HAVE BEEN HINTING AT A PATTERN SHIFT THAT HAS BEEN MIRRORED IN
THE RETURN TO A MORE ZONAL FLOW IN THE OPERATIONAL MODELS. PROBLEM
IS THAT THE SHIFT IS NOT HAPPENING...AND THE OSCILLATION FORECASTS
BASED ON ENSEMBLES ARE LOOKING MORE AND MORE DRASTIC...AND
UNLIKELY TO MAKE SUCH A VIOLENT SHIFT. THIS IS MORE OF A GLITCH IN
THE MED RANGE UNTIL THE MODELS QUIT STUMBLING OVER THE FIRST GUESS
BIAS.
SHORT TERM...TODAY AND TOMORROW...
A BRIEF BREAK FROM THE PRECIP EXPECTED FOR TODAY...HIGHS IN THE
20S AS THE NWRLY FLOW CONTINUES. POORLY SAMPLED NWRN CANADA AND
MASKING BANK OF CLOUDS AT THE TOP OF THE RIDGE ON WV MAY BE HIDING
EMBEDDED SHORTWAVES THAT MAY BRING FLURRIES OVER THE FA IN THE
SHORT TERM...BUT FOR NOW WILL KEEP THE FORECAST WITHOUT PRECIP
MENTION. TOMORROW SOUTHERLY FLOW SETS UP...USHERING IN SOME WARMER
TEMPS AT THE SFC...AND MELTING SOME OF THE SNOWPACK OVER THE CWA.
LONG TERM...THURSDAY THROUGH SATURDAY...
SLOW WARM UP CONTINUES THROUGH THURSDAY...THOUGH TRUNCATED BY THE
PASSAGE OF A FRONT WITH SOME RATHER COLD AIR BEHIND IT EARLY
MORNING FRIDAY. TIMING OF THE FRONT IS SHIFTING LATER...ENOUGH TO
ALTER THE MIN TEMPS THU NIGHT/FRI MORNING. BUT SLOWING THE
PROGRESSION OF THE SFC SYSTEM IS ALSO IN DIRECT OPPOSITION TO THE
ATTEMPT OF THE MODELS TO PUSH A MORE ZONAL FLOW INTO THE WEEKEND
OVER THE ERN HALF OF THE CONUS.
HJS
&&
.AVIATION...
ISSUED 1137 PM CST MON JAN 19 2009...FOR THE 06Z TAFS
SNOW SHOWERS ARE QUICKLY COMING TO AN END ACROSS CENTRAL
ILLINOIS...AS THE UPPER SHORTWAVE DROPS SOUTH OF THE CWA. FLURRIES
AND MVFR CIGS SHOULD PREVAIL THE REST OF THE NIGHT. SATELLITE
IMAGES ARE SHOWING BREAKS IN THE CLOUD COVER ACROSS S WIS AND N
IL. WENT WITH SOME VFR CIGS TO SHOW THAT TREND...BUT KEPT A
CEILING AT ALL SITES. PIA/BMI/CMI WILL HAVE THE BEST CHANCE AT
CLEARING SKIES BEFORE SUNRISE. GUID IS INDICATING MVFR CIGS THE
REST OF THE NIGHT...AND SPORADIC OBSERVATIONS UPSTREAM WOULD
SUPPORT THAT AS WELL.
WILL HOLD OFF ON WIDESPREAD CLEARING IN THE TAFS UNTIL MID DAY OR
AFTERNOON.
ANOTHER DISTURBANCE IS INDICATED IN THE 00Z MODELS THAT MAY AFFECT
THE EASTERN CWA...POSSIBLY CMI...WITH SOME SNOW TUES. WILL NOT
JUMP ON THAT JUST YET...AND KEEP THINGS VFR WITH NO CIG IN THE AFTERNOON.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 200537
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1137 PM CST MON JAN 19 2009
.DISCUSSION...
ISSUED 857 PM CST MON JAN 19 2009
THE H5 SHORTWAVE AND RESULTANT WEAK SURFACE TROUGH ARE TRIGGERING
WIDESPREAD LIGHT SNOW SHOWERS ACROSS C IL THIS EVENING. THE AREA OF
BEST FORCING IS PRIMARILY ACROSS THE AREA WEST OF I-57...CLOSER TO
THE AXIS OF CHANNELED VORTICITY. THE PRECIP IS MOST ENHANCED IN
THE GRADIENT OF DPVA ON THE CYCLONIC SHEAR SIDE OF THE VORT MAX.
THIS AREA OF FORCING IS EXPECTED TO SLIDE SOUTH AND WEST OF OUR
CWA SHORTLY AFTER MIDNIGHT...HELPING TO DIMINISH ACCUMULATING
SNOWS. OUR SW CWA MAY SEE SNOW LINGER FOR A TIME AFTER
MIDNIGHT...WHERE WE HAVE 20 POPS IN PLACE.
CLEARING TONIGHT SHOULD BE MUCH MORE LIMITED THAN LAST NIGHT...SO
LOWS SHOULD BE MORE STABLE. ONCE AGAIN...ANY CLEAR SPOTS WILL
ALLOW FOR TEMPS TO DROP DRAMATICALLY OVER SHORT PERIODS OF TIME
AND SHORT DISTANCES. WILL STAY THE COURSE FOR THE LOW TEMP GRID TO
CATCH THE PREVAILING EXPECTED TEMP CONDITIONS.
THE CLOUDS/WINDS AND REMAINDER OF THE DATABASE IS LOOKING OK. WILL
NOT MAKE MAJOR CHANGES THIS EVENING.
UPDATED GRIDS AND ZONES WILL BE AVAILABLE SHORTLY.
SHIMON
&&
.AVIATION...
ISSUED 1137 PM CST MON JAN 19 2009...FOR THE 06Z TAFS
SNOW SHOWERS ARE QUICKLY COMING TO AN END ACROSS CENTRAL
ILLINOIS...AS THE UPPER SHORTWAVE DROPS SOUTH OF THE CWA. FLURRIES
AND MVFR CIGS SHOULD PREVAIL THE REST OF THE NIGHT. SATELLITE
IMAGES ARE SHOWING BREAKS IN THE CLOUD COVER ACROSS S WIS AND N
IL. WENT WITH SOME VFR CIGS TO SHOW THAT TREND...BUT KEPT A
CEILING AT ALL SITES. PIA/BMI/CMI WILL HAVE THE BEST CHANCE AT
CLEARING SKIES BEFORE SUNRISE. GUID IS INDICATING MVFR CIGS THE
REST OF THE NIGHT...AND SPORADIC OBSERVATIONS UPSTREAM WOULD
SUPPORT THAT AS WELL.
WILL HOLD OFF ON WIDESPREAD CLEARING IN THE TAFS UNTIL MID DAY OR
AFTERNOON.
ANOTHER DISTURBANCE IS INDICATED IN THE 00Z MODELS THAT MAY AFFECT
THE EASTERN CWA...POSSIBLY CMI...WITH SOME SNOW TUES. WILL NOT
JUMP ON THAT JUST YET...AND KEEP THINGS VFR WITH NO CIG IN THE AFTERNOON.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 250 PM CST MON JAN 19 2009
IN THE SHORT TERM...THE MODELS ARE IN VERY GOOD AGREEMENT WITH
OVERALL PATTERN AND EXPECTED WEATHER NEXT 48HRS. THE MAIN CONCERN
DURING THIS PERIOD WILL BE THE AMOUNT OF SNOWFALL EXPECTED TONIGHT
AND AMOUNT OF WARM UP FOR WED AND THUR. IN THE LONG TERM...THE
EXTENDED MODELS LOOK VERY SIMILAR WITH THE EXPECTED WEATHER
PATTERN AND SOMEWHAT SIMILAR WITH THE NEXT SYSTEM EXPECTED LATER
PART OF THE WEEKEND AND EARLY NEXT WEEK. THE GFS HAS COME IN LINE
WITH WHAT THE ECMWF HAS BEEN SHOWING LAST SEVERAL RUNS. NEW
FORECAST WILL NOT BE MUCH DIFFERENT FROM CURRENT ONE WITH MODELS
MAINTAINING GOOD CONTINUITY FROM PREVIOUS RUNS. THEREFORE CURRENT
FORECAST CONFIDENCE IS HIGH.
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
FINAL SHORT WAVE IS DIVING DOWN FROM MN AND WILL PUSH INTO WESTERN
IL AND BRING ANOTHER SHOT OF LIGHT SNOW TONIGHT. LAST NIGHT EVENT
PRODUCE LITTLE MORE THAN EXPECTED BUT THIS EVENT TONIGHT DOES NOT
APPEAR AS VIGOROUS...AND THE TRACK IS FURTHER WEST. HOWEVER...
LIGHT SNOW IS LIKELY ACROSS THE WESTERN HALF OF THE AREA TONIGHT
BEFORE IT TAPERS OFF TO FLURRIES AFTER MIDNIGHT. HIGHEST
ACCUMULATION AMOUNTS WILL BE IN THE WEST AND SHOULD BE AROUND ONE
HALF INCH...WITH LIGHTER AMOUNTS TOWARD THE EAST. COULD BE SOME
LINGER FLURRIES TOMORROW MORNING AS MODELS INDICATE SOME DECENT
LOW LVL MOISTURE IN THE SOUTH DURING THE MORNING HOURS. AFTER
THIS...THE REST OF THE SHORT TERM WILL BE DRY AS SURFACE HIGH
PRESS BUILDS IN FROM THE WEST. THE UPPER LEVEL TROUGH WILL ALSO
QUICKLY MOVE EAST OF THE AREA AND THE UPPER PATTERN WILL BECOME
SOMEWHAT ZONAL...THOUGH FLOW WILL BE FROM THE NW. THIS SURFACE
HIGH PRSS RIDGE WILL MOVE EAST OF THE AREA WED MORNING WHICH WILL
BRING SOUTHWESTERLY SURFACE FLOW AND WAA TO THE REGION INTO
THURSDAY.
FOLLOWED GUIDANCE TEMPS CLOSE FOR THE SHORT TERM...EVEN FOR THE
ABOVE NORMAL TEMP FORECAST FOR THUR.
LONG TERM...FRIDAY THROUGH MONDAY
LONG TERM MODELS INDICATE THAT A STRONGER/DRY SFC FRONT WILL DROP
THROUGH THE AREA ON FRIDAY. THIS WILL BRING A RETURN TO THE COLDER
AND BELOW NORMAL TEMPS FOR THE WEEKEND. COMBINED WITH THE ZONAL
WEATHER PATTERN...THE AREA WILL NOT SEE ANY PCPN FOR MOST OF THE
WEEKEND. THEN THE MODELS ARE SHOWING CYCLOGENESIS OCCURRING SUNDAY
NIGHT IN THE WESTERN PLAINS. AN ASSOCIATED WARM FRONT WILL LIKELY
DEVELOP SOUTH OF THE CWA AND SPREAD PCPN ACROSS PARTS OF IL
BEGINNING SUNDAY NIGHT. BASED ON EXPECTED TEMP PROFILE AT THE
TIME...P-TYPE WILL BEGIN IN THE FORM OF SNOW. AS LONG AS ENTIRE
SYSTEM AND FRONT REMAINS SOUTH OF THE AREA...ALL PCPN SHOULD BE
SNOW. HOWEVER...MONDAY`S PCPN COULD BE IN FORM OF RAIN SO WILL
KEEP P-TYPE SIMPLE FOR NOW AND JUST HAVE RAIN OR SNOW FOR MONDAY.
TEMPS WILL REMAIN COOL UNTIL LATE IN THE PERIOD WHEN MODELS
INDICATE SOME WARMING. NEW MEX GUIDANCE LOOKS FAIRLY CLOSE.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 200258
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
858 PM CST MON JAN 19 2009
.DISCUSSION...
ISSUED 857 PM CST MON JAN 19 2009
THE H5 SHORTWAVE AND RESULTANT WEAK SURFACE TROUGH ARE TRIGGERING
WIDESPREAD LIGHT SNOW SHOWERS ACROSS C IL THIS EVENING. THE AREA OF
BEST FORCING IS PRIMARILY ACROSS THE AREA WEST OF I-57...CLOSER TO
THE AXIS OF CHANNELED VORTICITY. THE PRECIP IS MOST ENHANCED IN
THE GRADIENT OF DPVA ON THE CYCLONIC SHEAR SIDE OF THE VORT MAX.
THIS AREA OF FORCING IS EXPECTED TO SLIDE SOUTH AND WEST OF OUR
CWA SHORTLY AFTER MIDNIGHT...HELPING TO DIMINISH ACCUMULATING
SNOWS. OUR SW CWA MAY SEE SNOW LINGER FOR A TIME AFTER
MIDNIGHT...WHERE WE HAVE 20 POPS IN PLACE.
CLEARING TONIGHT SHOULD BE MUCH MORE LIMITED THAN LAST NIGHT...SO
LOWS SHOULD BE MORE STABLE. ONCE AGAIN...ANY CLEAR SPOTS WILL
ALLOW FOR TEMPS TO DROP DRAMATICALLY OVER SHORT PERIODS OF TIME
AND SHORT DISTANCES. WILL STAY THE COURSE FOR THE LOW TEMP GRID TO
CATCH THE PREVAILING EXPECTED TEMP CONDITIONS.
THE CLOUDS/WINDS AND REMAINDER OF THE DATABASE IS LOOKING OK. WILL
NOT MAKE MAJOR CHANGES THIS EVENING.
UPDATED GRIDS AND ZONES WILL BE AVAILABLE SHORTLY.
SHIMON
&&
.AVIATION...
ISSUED 540 PM CST MON JAN 19 2009...FOR THE 00Z TAFS
A WEAK SHORTWAVE IS PRODUCING SNOW IN OUR NW CWA AS OF 5 PM. THIS
SNOW WILL EXPAND TO COVER THE REMAINDER OF THE CWA BY MID
EVENING...ESPECIALLY THE WESTERN TWO THIRDS. EAST OF I-57 WILL SEE
THE LEAST AMOUNTS OF SNOW...INCLUDING CMI. WILL HIT PIA AND SPI
THE HARDEST FOR VIS AND CIGS...WITH IFR VIS AND MVFR CIGS. THE
OTHER SITES SHOULD REMAIN MVFR FOR VIS AND CIGS THIS EVENING.
SATELLITE TRENDS INDICATE SNOW MAY LINGER BEYOND MIDNIGHT...BUT
GFS GUID CONTINUES TO END PRECIP BEFORE MIDNIGHT. NAM-WRF GUID
KEEPS PRECIP AROUND UNTIL 11-13Z TUES MORNING.
SENT TAFS OUT WITHOUT LATER NIGHT PRECIP...BUT MAY BE UPDATING TO
INCLUDE A LONGER PERIOD OF SNOW AS THE RADAR AND SATELLITE TRENDS
UPSTREAM DICTATE.
WINDS WILL REMAIN NORTH TONIGHT...THEN BACK TO THE NORTHWEST BY
NOON TUESDAY...BEHIND THE SHORTWAVE. CIGS ARE A TOUGH CALL DURING
THE DAY TUES...AS NAM GUID KEEPS IFR CIGS INTO TUES
EVENING...WHILE GFS KEEPS MVFR. WILL STAY WITH MVFR FOR
NOW...BASED ON RH PROFILES FROM UPSTREAM SOUNDINGS.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 250 PM CST MON JAN 19 2009
IN THE SHORT TERM...THE MODELS ARE IN VERY GOOD AGREEMENT WITH
OVERALL PATTERN AND EXPECTED WEATHER NEXT 48HRS. THE MAIN CONCERN
DURING THIS PERIOD WILL BE THE AMOUNT OF SNOWFALL EXPECTED TONIGHT
AND AMOUNT OF WARM UP FOR WED AND THUR. IN THE LONG TERM...THE
EXTENDED MODELS LOOK VERY SIMILAR WITH THE EXPECTED WEATHER
PATTERN AND SOMEWHAT SIMILAR WITH THE NEXT SYSTEM EXPECTED LATER
PART OF THE WEEKEND AND EARLY NEXT WEEK. THE GFS HAS COME IN LINE
WITH WHAT THE ECMWF HAS BEEN SHOWING LAST SEVERAL RUNS. NEW
FORECAST WILL NOT BE MUCH DIFFERENT FROM CURRENT ONE WITH MODELS
MAINTAINING GOOD CONTINUITY FROM PREVIOUS RUNS. THEREFORE CURRENT
FORECAST CONFIDENCE IS HIGH.
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
FINAL SHORT WAVE IS DIVING DOWN FROM MN AND WILL PUSH INTO WESTERN
IL AND BRING ANOTHER SHOT OF LIGHT SNOW TONIGHT. LAST NIGHT EVENT
PRODUCE LITTLE MORE THAN EXPECTED BUT THIS EVENT TONIGHT DOES NOT
APPEAR AS VIGOROUS...AND THE TRACK IS FURTHER WEST. HOWEVER...
LIGHT SNOW IS LIKELY ACROSS THE WESTERN HALF OF THE AREA TONIGHT
BEFORE IT TAPERS OFF TO FLURRIES AFTER MIDNIGHT. HIGHEST
ACCUMULATION AMOUNTS WILL BE IN THE WEST AND SHOULD BE AROUND ONE
HALF INCH...WITH LIGHTER AMOUNTS TOWARD THE EAST. COULD BE SOME
LINGER FLURRIES TOMORROW MORNING AS MODELS INDICATE SOME DECENT
LOW LVL MOISTURE IN THE SOUTH DURING THE MORNING HOURS. AFTER
THIS...THE REST OF THE SHORT TERM WILL BE DRY AS SURFACE HIGH
PRESS BUILDS IN FROM THE WEST. THE UPPER LEVEL TROUGH WILL ALSO
QUICKLY MOVE EAST OF THE AREA AND THE UPPER PATTERN WILL BECOME
SOMEWHAT ZONAL...THOUGH FLOW WILL BE FROM THE NW. THIS SURFACE
HIGH PRSS RIDGE WILL MOVE EAST OF THE AREA WED MORNING WHICH WILL
BRING SOUTHWESTERLY SURFACE FLOW AND WAA TO THE REGION INTO
THURSDAY.
FOLLOWED GUIDANCE TEMPS CLOSE FOR THE SHORT TERM...EVEN FOR THE
ABOVE NORMAL TEMP FORECAST FOR THUR.
LONG TERM...FRIDAY THROUGH MONDAY
LONG TERM MODELS INDICATE THAT A STRONGER/DRY SFC FRONT WILL DROP
THROUGH THE AREA ON FRIDAY. THIS WILL BRING A RETURN TO THE COLDER
AND BELOW NORMAL TEMPS FOR THE WEEKEND. COMBINED WITH THE ZONAL
WEATHER PATTERN...THE AREA WILL NOT SEE ANY PCPN FOR MOST OF THE
WEEKEND. THEN THE MODELS ARE SHOWING CYCLOGENESIS OCCURRING SUNDAY
NIGHT IN THE WESTERN PLAINS. AN ASSOCIATED WARM FRONT WILL LIKELY
DEVELOP SOUTH OF THE CWA AND SPREAD PCPN ACROSS PARTS OF IL
BEGINNING SUNDAY NIGHT. BASED ON EXPECTED TEMP PROFILE AT THE
TIME...P-TYPE WILL BEGIN IN THE FORM OF SNOW. AS LONG AS ENTIRE
SYSTEM AND FRONT REMAINS SOUTH OF THE AREA...ALL PCPN SHOULD BE
SNOW. HOWEVER...MONDAY`S PCPN COULD BE IN FORM OF RAIN SO WILL
KEEP P-TYPE SIMPLE FOR NOW AND JUST HAVE RAIN OR SNOW FOR MONDAY.
TEMPS WILL REMAIN COOL UNTIL LATE IN THE PERIOD WHEN MODELS
INDICATE SOME WARMING. NEW MEX GUIDANCE LOOKS FAIRLY CLOSE.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 192341
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
541 PM CST MON JAN 19 2009
.DISCUSSION...
ISSUED 250 PM CST MON JAN 19 2009
IN THE SHORT TERM...THE MODELS ARE IN VERY GOOD AGREEMENT WITH
OVERALL PATTERN AND EXPECTED WEATHER NEXT 48HRS. THE MAIN CONCERN
DURING THIS PERIOD WILL BE THE AMOUNT OF SNOWFALL EXPECTED TONIGHT
AND AMOUNT OF WARM UP FOR WED AND THUR. IN THE LONG TERM...THE
EXTENDED MODELS LOOK VERY SIMILAR WITH THE EXPECTED WEATHER
PATTERN AND SOMEWHAT SIMILAR WITH THE NEXT SYSTEM EXPECTED LATER
PART OF THE WEEKEND AND EARLY NEXT WEEK. THE GFS HAS COME IN LINE
WITH WHAT THE ECMWF HAS BEEN SHOWING LAST SEVERAL RUNS. NEW
FORECAST WILL NOT BE MUCH DIFFERENT FROM CURRENT ONE WITH MODELS
MAINTAINING GOOD CONTINUITY FROM PREVIOUS RUNS. THEREFORE CURRENT
FORECAST CONFIDENCE IS HIGH.
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
FINAL SHORT WAVE IS DIVING DOWN FROM MN AND WILL PUSH INTO WESTERN
IL AND BRING ANOTHER SHOT OF LIGHT SNOW TONIGHT. LAST NIGHT EVENT
PRODUCE LITTLE MORE THAN EXPECTED BUT THIS EVENT TONIGHT DOES NOT
APPEAR AS VIGOROUS...AND THE TRACK IS FURTHER WEST. HOWEVER...
LIGHT SNOW IS LIKELY ACROSS THE WESTERN HALF OF THE AREA TONIGHT
BEFORE IT TAPERS OFF TO FLURRIES AFTER MIDNIGHT. HIGHEST
ACCUMULATION AMOUNTS WILL BE IN THE WEST AND SHOULD BE AROUND ONE
HALF INCH...WITH LIGHTER AMOUNTS TOWARD THE EAST. COULD BE SOME
LINGER FLURRIES TOMORROW MORNING AS MODELS INDICATE SOME DECENT
LOW LVL MOISTURE IN THE SOUTH DURING THE MORNING HOURS. AFTER
THIS...THE REST OF THE SHORT TERM WILL BE DRY AS SURFACE HIGH
PRESS BUILDS IN FROM THE WEST. THE UPPER LEVEL TROUGH WILL ALSO
QUICKLY MOVE EAST OF THE AREA AND THE UPPER PATTERN WILL BECOME
SOMEWHAT ZONAL...THOUGH FLOW WILL BE FROM THE NW. THIS SURFACE
HIGH PRSS RIDGE WILL MOVE EAST OF THE AREA WED MORNING WHICH WILL
BRING SOUTHWESTERLY SURFACE FLOW AND WAA TO THE REGION INTO
THURSDAY.
FOLLOWED GUIDANCE TEMPS CLOSE FOR THE SHORT TERM...EVEN FOR THE
ABOVE NORMAL TEMP FORECAST FOR THUR.
LONG TERM...FRIDAY THROUGH MONDAY
LONG TERM MODELS INDICATE THAT A STRONGER/DRY SFC FRONT WILL DROP
THROUGH THE AREA ON FRIDAY. THIS WILL BRING A RETURN TO THE COLDER
AND BELOW NORMAL TEMPS FOR THE WEEKEND. COMBINED WITH THE ZONAL
WEATHER PATTERN...THE AREA WILL NOT SEE ANY PCPN FOR MOST OF THE
WEEKEND. THEN THE MODELS ARE SHOWING CYCLOGENESIS OCCURRING SUNDAY
NIGHT IN THE WESTERN PLAINS. AN ASSOCIATED WARM FRONT WILL LIKELY
DEVELOP SOUTH OF THE CWA AND SPREAD PCPN ACROSS PARTS OF IL
BEGINNING SUNDAY NIGHT. BASED ON EXPECTED TEMP PROFILE AT THE
TIME...P-TYPE WILL BEGIN IN THE FORM OF SNOW. AS LONG AS ENTIRE
SYSTEM AND FRONT REMAINS SOUTH OF THE AREA...ALL PCPN SHOULD BE
SNOW. HOWEVER...MONDAY`S PCPN COULD BE IN FORM OF RAIN SO WILL
KEEP P-TYPE SIMPLE FOR NOW AND JUST HAVE RAIN OR SNOW FOR MONDAY.
TEMPS WILL REMAIN COOL UNTIL LATE IN THE PERIOD WHEN MODELS
INDICATE SOME WARMING. NEW MEX GUIDANCE LOOKS FAIRLY CLOSE.
AUTEN
&&
.AVIATION...
ISSUED 540 PM CST MON JAN 19 2009...FOR THE 00Z TAFS
A WEAK SHORTWAVE IS PRODUCING SNOW IN OUR NW CWA AS OF 5 PM. THIS
SNOW WILL EXPAND TO COVER THE REMAINDER OF THE CWA BY MID
EVENING...ESPECIALLY THE WESTERN TWO THIRDS. EAST OF I-57 WILL SEE
THE LEAST AMOUNTS OF SNOW...INCLUDING CMI. WILL HIT PIA AND SPI
THE HARDEST FOR VIS AND CIGS...WITH IFR VIS AND MVFR CIGS. THE
OTHER SITES SHOULD REMAIN MVFR FOR VIS AND CIGS THIS EVENING.
SATELLITE TRENDS INDICATE SNOW MAY LINGER BEYOND MIDNIGHT...BUT
GFS GUID CONTINUES TO END PRECIP BEFORE MIDNIGHT. NAM-WRF GUID
KEEPS PRECIP AROUND UNTIL 11-13Z TUES MORNING.
SENT TAFS OUT WITHOUT LATER NIGHT PRECIP...BUT MAY BE UPDATING TO
INCLUDE A LONGER PERIOD OF SNOW AS THE RADAR AND SATELLITE TRENDS
UPSTREAM DICTATE.
WINDS WILL REMAIN NORTH TONIGHT...THEN BACK TO THE NORTHWEST BY
NOON TUESDAY...BEHIND THE SHORTWAVE. CIGS ARE A TOUGH CALL DURING
THE DAY TUES...AS NAM GUID KEEPS IFR CIGS INTO TUES
EVENING...WHILE GFS KEEPS MVFR. WILL STAY WITH MVFR FOR
NOW...BASED ON RH PROFILES FROM UPSTREAM SOUNDINGS.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 192050
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
250 PM CST MON JAN 19 2009
.DISCUSSION...
ISSUED 250 PM CST MON JAN 19 2009
IN THE SHORT TERM...THE MODELS ARE IN VERY GOOD AGREEMENT WITH
OVERALL PATTERN AND EXPECTED WEATHER NEXT 48HRS. THE MAIN CONCERN
DURING THIS PERIOD WILL BE THE AMOUNT OF SNOWFALL EXPECTED TONIGHT
AND AMOUNT OF WARM UP FOR WED AND THUR. IN THE LONG TERM...THE
EXTENDED MODELS LOOK VERY SIMILAR WITH THE EXPECTED WEATHER
PATTERN AND SOMEWHAT SIMILAR WITH THE NEXT SYSTEM EXPECTED LATER
PART OF THE WEEKEND AND EARLY NEXT WEEK. THE GFS HAS COME IN LINE
WITH WHAT THE ECMWF HAS BEEN SHOWING LAST SEVERAL RUNS. NEW
FORECAST WILL NOT BE MUCH DIFFERENT FROM CURRENT ONE WITH MODELS
MAINTAINING GOOD CONTINUITY FROM PREVIOUS RUNS. THEREFORE CURRENT
FORECAST CONFIDENCE IS HIGH.
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
FINAL SHORT WAVE IS DIVING DOWN FROM MN AND WILL PUSH INTO WESTERN
IL AND BRING ANOTHER SHOT OF LIGHT SNOW TONIGHT. LAST NIGHT EVENT
PRODUCE LITTLE MORE THAN EXPECTED BUT THIS EVENT TONIGHT DOES NOT
APPEAR AS VIGOROUS...AND THE TRACK IS FURTHER WEST. HOWEVER...
LIGHT SNOW IS LIKELY ACROSS THE WESTERN HALF OF THE AREA TONIGHT
BEFORE IT TAPERS OFF TO FLURRIES AFTER MIDNIGHT. HIGHEST
ACCUMULATION AMOUNTS WILL BE IN THE WEST AND SHOULD BE AROUND ONE
HALF INCH...WITH LIGHTER AMOUNTS TOWARD THE EAST. COULD BE SOME
LINGER FLURRIES TOMORROW MORNING AS MODELS INDICATE SOME DECENT
LOW LVL MOISTURE IN THE SOUTH DURING THE MORNING HOURS. AFTER
THIS...THE REST OF THE SHORT TERM WILL BE DRY AS SURFACE HIGH
PRESS BUILDS IN FROM THE WEST. THE UPPER LEVEL TROUGH WILL ALSO
QUICKLY MOVE EAST OF THE AREA AND THE UPPER PATTERN WILL BECOME
SOMEWHAT ZONAL...THOUGH FLOW WILL BE FROM THE NW. THIS SURFACE
HIGH PRSS RIDGE WILL MOVE EAST OF THE AREA WED MORNING WHICH WILL
BRING SOUTHWESTERLY SURFACE FLOW AND WAA TO THE REGION INTO
THURSDAY.
FOLLOWED GUIDANCE TEMPS CLOSE FOR THE SHORT TERM...EVEN FOR THE
ABOVE NORMAL TEMP FORECAST FOR THUR.
LONG TERM...FRIDAY THROUGH MONDAY
LONG TERM MODELS INDICATE THAT A STRONGER/DRY SFC FRONT WILL DROP
THROUGH THE AREA ON FRIDAY. THIS WILL BRING A RETURN TO THE COLDER
AND BELOW NORMAL TEMPS FOR THE WEEKEND. COMBINED WITH THE ZONAL
WEATHER PATTERN...THE AREA WILL NOT SEE ANY PCPN FOR MOST OF THE
WEEKEND. THEN THE MODELS ARE SHOWING CYCLOGENESIS OCCURRING SUNDAY
NIGHT IN THE WESTERN PLAINS. AN ASSOCIATED WARM FRONT WILL LIKELY
DEVELOP SOUTH OF THE CWA AND SPREAD PCPN ACROSS PARTS OF IL
BEGINNING SUNDAY NIGHT. BASED ON EXPECTED TEMP PROFILE AT THE
TIME...P-TYPE WILL BEGIN IN THE FORM OF SNOW. AS LONG AS ENTIRE
SYSTEM AND FRONT REMAINS SOUTH OF THE AREA...ALL PCPN SHOULD BE
SNOW. HOWEVER...MONDAY`S PCPN COULD BE IN FORM OF RAIN SO WILL
KEEP P-TYPE SIMPLE FOR NOW AND JUST HAVE RAIN OR SNOW FOR MONDAY.
TEMPS WILL REMAIN COOL UNTIL LATE IN THE PERIOD WHEN MODELS
INDICATE SOME WARMING. NEW MEX GUIDANCE LOOKS FAIRLY CLOSE.
AUTEN
&&
.AVIATION...
ISSUED 1150 AM CST MON JAN 19 2009
ANOTHER STRONG SHORT WAVE OVER MN WILL DIVE SSE ACROSS IA THIS
AFTERNOON AND MO THIS EVENING...BRINGING LIGHT SNOW BACK INTO THE
CENTRAL IL TERMINALS ESPECIALLY WEST OF I-57/CMI. MOSTLY CLEAR
SKIES WILL BECOME MOSTLY CLOUDY TO OVERCAST DURING THE AFTERNOON
AS MID LEVEL CLOUDS INCREASING FROM THE NNW. CURULE ALSO SHOWS
SCATTERED TO BROKEN STRATOCU CLOUDS FROM 2.5 TO 5K FT DEVELOPING
BY MID/LATE AFTERNOON. FLURRIES POSSIBLE LATE THIS AFTERNOON THEN
HAVE STEADY LIGHT SNOW WEST OF CMI THIS EVENING...STARTING EARLY
THIS EVENING FROM 00Z-02Z AND ENDING BY 06Z/MIDNIGHT. LOWEST
VISIBILITIES OF 1 TO 2 MILES AT WESTERN TAF SITES OF PIA AND SPI
CLOSER TO SHORT WAVE PASSING OVER MO WHILE CMI VSBY ONLY 4 TO 6
MILES. MVFR CEILINGS LIKELY THIS EVENING AS WELL WITH LIGHT SNOW.
STRONG SHORT WAVE QUICKLY PASSES QUICKLY INTO AR...MS...AL AND GA
BY DAWN FRI. COULD BE ENOUGH SUBSIDENCE IT ITS WAKE TO SCATTERED
OUT LOW CLOUDS LATE TONIGHT/TUE MORNING AS HAS BEEN THE CASE THIS
MORNING BUT FOR NOW LIFTED CEILINGS UP TO VFR TUE MORNING. NW
WINDS 7 TO 10 KTS INTO THIS EVENING TURN NNW AT 10 TO 15 KTS BY
OVERNIGHT INTO TUE MORNING.
HUETTL
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 191751
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1151 AM CST MON JAN 19 2009
.DISCUSSION...
ISSUED 1045 AM CST MON JAN 19 2009
ADJUSTED THE SKY COVER TODAY WITH MORE SUNSHINE THIS MORNING WITH
INCREASING CLOUDS IN THE AFTERNOON. REST OF FORECAST LOOKS ON
TRACK AND CONTINUE CHANCE OF LIGHT SNOW LATER THIS AFTERNOON OVER
THE IL RIVER VALLEY WITH BRUNT OF LIGHT SNOW ARRIVING DURING THIS
EVENING. HIGHS IN THE LOW TO MID 20S WHICH IS NEARLY 10 DEGREES
COOLER THAN NORMAL FOR MID JAN. NW WINDS OF 7 TO 15 MPH.
MOSTLY SUNNY SKIES PREVAILED ACROSS MUCH OF IL THIS MORNING THOUGH
LAKE EFFECT LOW CLOUDS MOVING SOUTH FROM LAKE MI INTO NE VERMILION
COUNTY NEARING DANVILLE. WEAK HIGH PRESSURE RIDGE OF 1017 MB WAS
NEAR THE MS VALLEY WHILE MUCH STRONGER HIGH PRESSURE OF 1040 TO
1050 MB WAS OVER THE ROCKIES. 1003 MB LOW PRESSURE WAS JUST NORTH
OF LAKE ERIE OVER THE SE ONTARIO PENISULA. HIGHLY AMPLIFIED UPPER
LEVEL PATTERN OVER NORTH AMERICA WITH LARGE/DEEP 516 DM 500 MB LOW
WAS OVER NE LAKE ERIE WITH A VERY LARGE UPPER LEVEL TROF OVER THE
EASTERN STATES EAST OF THE ROCKIES AND STRONG UPPER LEVEL RIDGE
OVER WESTERN NORTH AMERICA. EARLY MORNING LOWS IN THE SINGLES
DIGITS OVER CENTRAL IL WITH LOWER TEENS SE OF I-70 AND FROM
SPRINGFIELD SW. TEMPS HAVE ONLY RECOVERED INTO THE LOWER TEENS NE
AND UPPER TEENS SW.
SHORT RANGE MODELS SIMILAR IN TAKING ANOTHER FAIRLY STRONG SHORT
WAVE OVER MN SSE ACROSS IA THIS AFTERNOON AND MO THIS EVENING.
SOME LIGHT SNOW COULD MOVE INTO THE IL RIVER VALLEY ESPECIALLY NW
OF THE IL RIVER LATE THIS AFTERNOON THEN SPREAD SOUTH ACROSS
CENTRAL/WESTERN IL THIS EVENING. EASTERN IL EAST OF I-57 DOES NOT
APPER TO HAVE AS GOOD OF A CHANCE OF LIGHT SNOW THIS EVENING.
HIGHS THIS AFTERNOON IN THE LOW TO MID 20S.
HUETTL
&&
.AVIATION...
ISSUED 1150 AM CST MON JAN 19 2009
ANOTHER STRONG SHORT WAVE OVER MN WILL DIVE SSE ACROSS IA THIS
AFTERNOON AND MO THIS EVENING...BRINGING LIGHT SNOW BACK INTO THE
CENTRAL IL TERMINALS ESPECIALLY WEST OF I-57/CMI. MOSTLY CLEAR
SKIES WILL BECOME MOSTLY CLOUDY TO OVERCAST DURING THE AFTERNOON
AS MID LEVEL CLOUDS INCREASING FROM THE NNW. CURULE ALSO SHOWS
SCATTERED TO BROKEN STRATOCU CLOUDS FROM 2.5 TO 5K FT DEVELOPING
BY MID/LATE AFTERNOON. FLURRIES POSSIBLE LATE THIS AFTERNOON THEN
HAVE STEADY LIGHT SNOW WEST OF CMI THIS EVENING...STARTING EARLY
THIS EVENING FROM 00Z-02Z AND ENDING BY 06Z/MIDNIGHT. LOWEST
VISIBILITIES OF 1 TO 2 MILES AT WESTERN TAF SITES OF PIA AND SPI
CLOSER TO SHORT WAVE PASSING OVER MO WHILE CMI VSBY ONLY 4 TO 6
MILES. MVFR CEILINGS LIKELY THIS EVENING AS WELL WITH LIGHT SNOW.
STRONG SHORT WAVE QUICKLY PASSES QUICKLY INTO AR...MS...AL AND GA
BY DAWN FRI. COULD BE ENOUGH SUBSIDENCE IT ITS WAKE TO SCATTERED
OUT LOW CLOUDS LATE TONIGHT/TUE MORNING AS HAS BEEN THE CASE THIS
MORNING BUT FOR NOW LIFTED CEILINGS UP TO VFR TUE MORNING. NW
WINDS 7 TO 10 KTS INTO THIS EVENING TURN NNW AT 10 TO 15 KTS BY
OVERNIGHT INTO TUE MORNING.
HUETTL
&&
.PREV DISCUSSION...
ISSUED 315 AM CST MON JAN 19 2009
THE CONUS EAST OF THE ROCKIES STILL DOMINATED BY A RATHER DEEP
UPPER LEVEL TROF. FLOW AT THE SFC COMING OUT OF THE NORTH AND
HELPING TO PUSH THE REMNANTS OF LAST NIGHTS SNOWFALL CLEAR OF THE
CWA. SOME LOW LEVEL CLOUDS STARTING TO DRIFT SOUTH OF LAKE
MICHIGAN ALONG THE ILLINOIS INDIANA BORDER. TEMPS DROPPING QUICKLY
UNDER THE CLEARING SKIES. FIRST SMALL CHALLENGE WILL BE THE TEMPS
TODAY AND HOW QUICKLY THEY WILL REBOUND...BUT THE BIGGER CHALLENGE
WILL BE THE NEXT SHORTWAVE THAT IS MOVING INTO THE FORECAST AREA
LATE THIS AFTERNOON/EARLY THIS EVENING. STILL GOING WITH THE NAM
IN THE SHORT TERM...AND THE ECMWF FOR THE MED RANGE...WHICH
RESULTS IN THE FORECAST BEING A BIT OFF FROM THE MEX GUIDANCE
GOING INTO NEXT WEEKEND.
SHORT TERM...TODAY AND TOMORROW...
TEMPS HAVE A LONG WAY TO GO TO MAKE IT TO TODAYS HIGHS. HAVE
DROPPED THEM JUST A TOUCH...BUT PLENTY OF MORNING SUNSHINE SHOULD
MORE THAN MAKE UP FOR THE PREDAWN PLUMMET. ANOTHER WAVE ON ITS WAY
TO BRING SNOW TO THE FA LATER THIS AFTERNOON/EVENING. WAVE VISIBLE
AROUND 06Z MON JUST SW OF THE HUDSON BAY. ACCORDING TO 00Z MODEL
RUNS... IT WAS JUST A TOUCH EARLY. HOWEVER...THE 06Z RUN OF THE
NAM PICKED UP ON THIS...AND STILL KEPT THE MAJORITY OF THE SNOW IN
FOR BTWN 00Z AND 06Z TONIGHT. CONCERNED THAT THIS MIGHT JUST BE A
FIRST GUESS BLEND FOR THE MODEL...HAVE INCREASED POPS PRIOR TO 00Z
IN THE NW IN CASE OF AN EARLIER ARRIVAL OF THE PRECIP. AFTER
MIDNIGHT...MAY SEE A SIMILAR SITUATION TO TONIGHT TAKE SHAPE...AND
HAVE DROPPED THE TEMPS SLIGHTLY IN COMPARISON TO ISC GRIDS.
TUESDAY AND TUESDAY NIGHT A BIT QUIETER...THOUGH STILL COLD WITH
THE PATTERN SHIFT TAKING ITS TIME GETTING OUT OF THE DEEP TROF
OVER THE ERN CONUS.
LONG TERM...WEDNESDAY THROUGH FRIDAY...
OVERNIGHT TUESDAY THE WINDS WILL COME AROUND TO THE SOUTH...THOUGH
LLVL WAA DOES NOT REALLY GET GOING UNTIL WEDNESDAY...AND THE TEMPS
REFLECT THAT. MAX TEMPS ABOVE FREEZING FOR WED AND THU SHOULD GET
SOME DECENT MELTING OF THE SNOWPACK AREAS GOING. PROBLEM MIGHT BE
AT NIGHT WITH THE TEMPS DROPPING DOWN BELOW FREEZING...WILL SEE A
MELTING/ICE SITUATION DEVELOP WITH THE DIURNAL TREND. ANOTHER COLD
SHOT OF AIR EXPECTED FRIDAY NIGHT AS THE WARMING TREND COMES TO AN
END.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 190930
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
330 AM CST MON JAN 19 2009
.DISCUSSION...
ISSUED 315 AM CST MON JAN 19 2009
THE CONUS EAST OF THE ROCKIES STILL DOMINATED BY A RATHER DEEP
UPPER LEVEL TROF. FLOW AT THE SFC COMING OUT OF THE NORTH AND
HELPING TO PUSH THE REMNANTS OF LAST NIGHTS SNOWFALL CLEAR OF THE
CWA. SOME LOW LEVEL CLOUDS STARTING TO DRIFT SOUTH OF LAKE
MICHIGAN ALONG THE ILLINOIS INDIANA BORDER. TEMPS DROPPING QUICKLY
UNDER THE CLEARING SKIES. FIRST SMALL CHALLENGE WILL BE THE TEMPS
TODAY AND HOW QUICKLY THEY WILL REBOUND...BUT THE BIGGER CHALLENGE
WILL BE THE NEXT SHORTWAVE THAT IS MOVING INTO THE FORECAST AREA
LATE THIS AFTERNOON/EARLY THIS EVENING. STILL GOING WITH THE NAM
IN THE SHORT TERM...AND THE ECMWF FOR THE MED RANGE...WHICH
RESULTS IN THE FORECAST BEING A BIT OFF FROM THE MEX GUIDANCE
GOING INTO NEXT WEEKEND.
SHORT TERM...TODAY AND TOMORROW...
TEMPS HAVE A LONG WAY TO GO TO MAKE IT TO TODAYS HIGHS. HAVE
DROPPED THEM JUST A TOUCH...BUT PLENTY OF MORNING SUNSHINE SHOULD
MORE THAN MAKE UP FOR THE PREDAWN PLUMMET. ANOTHER WAVE ON ITS WAY
TO BRING SNOW TO THE FA LATER THIS AFTERNOON/EVENING. WAVE VISIBLE
AROUND 06Z MON JUST SW OF THE HUDSON BAY. ACCORDING TO 00Z MODEL
RUNS... IT WAS JUST A TOUCH EARLY. HOWEVER...THE 06Z RUN OF THE
NAM PICKED UP ON THIS...AND STILL KEPT THE MAJORITY OF THE SNOW IN
FOR BTWN 00Z AND 06Z TONIGHT. CONCERNED THAT THIS MIGHT JUST BE A
FIRST GUESS BLEND FOR THE MODEL...HAVE INCREASED POPS PRIOR TO 00Z
IN THE NW IN CASE OF AN EARLIER ARRIVAL OF THE PRECIP. AFTER
MIDNIGHT...MAY SEE A SIMILAR SITUATION TO TONIGHT TAKE SHAPE...AND
HAVE DROPPED THE TEMPS SLIGHTLY IN COMPARISON TO ISC GRIDS.
TUESDAY AND TUESDAY NIGHT A BIT QUIETER...THOUGH STILL COLD WITH
THE PATTERN SHIFT TAKING ITS TIME GETTING OUT OF THE DEEP TROF
OVER THE ERN CONUS.
LONG TERM...WEDNESDAY THROUGH FRIDAY...
OVERNIGHT TUESDAY THE WINDS WILL COME AROUND TO THE SOUTH...THOUGH
LLVL WAA DOES NOT REALLY GET GOING UNTIL WEDNESDAY...AND THE TEMPS
REFLECT THAT. MAX TEMPS ABOVE FREEZING FOR WED AND THU SHOULD GET
SOME DECENT MELTING OF THE SNOWPACK AREAS GOING. PROBLEM MIGHT BE
AT NIGHT WITH THE TEMPS DROPPING DOWN BELOW FREEZING...WILL SEE A
MELTING/ICE SITUATION DEVELOP WITH THE DIURNAL TREND. ANOTHER COLD
SHOT OF AIR EXPECTED FRIDAY NIGHT AS THE WARMING TREND COMES TO AN
END.
HJS
&&
.AVIATION...
ISSUED 1150 PM CST SUN JAN 18 2009...FOR THE 06Z TAFS
THE SHORTWAVE SNOW BANDS ARE ALMOST SOUTH OF ALL TAF SITES.
SPI/DEC WILL SEE A BRIEF PERIOD OF SNOW EARLY IN THE TAF
FCST...BUT BY 08Z ALL SNOW SHOULD BE DONE. MVFR CIGS SHOULD BE
LIFTING AT SPI AND DEC SOON. THE OTHER SITES ALL HAVE VFR CIGS OR
NO CIGS AND THEY SHOULD REMAIN THAT WAY UNTIL DURING THE DAY MONDAY.
THE NEXT CLIPPER IS POISED TO QUICKLY DROP SOUTH OUT OF CANADA
MONDAY AFTERNOON...AND PRODUCE A PERIOD OF SNOW MONDAY EVENING IN
CENTRAL IL. THE NEW 00Z GUID IS SHOWING A FEW TENTHS TO A HALF
INCH OF SNOW POSSIBLE. WILL GO WITH A PREVAILING MVFR VIS AND CIG
BEGINNING AT 00Z IN PIA AND PROGRESSING SOUTH DURING THE EVENING.
NORTH WINDS WILL PREVAIL OVER THE NEXT 24 HRS.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 190550
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1150 PM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 855 PM CST SUN JAN 18 2009
SNOW BANDS HAVE BEEN VIGOROUS AT TIMES THIS EVENING...BUT THE
TRANSIENT NATURE OF THE BANDS HAS KEPT SNOW TOTALS IN ANY ONE AREA
ONLY AROUND AN INCH. SATELLITE AND RADAR TRENDS SHOW THE
ACCUMULATING SNOW WILL ONLY LAST FOR A COUPLE MORE HOURS. AS OF
845 PM...THE BACK EDGE HAS ALREADY REACHED A LINE FROM GALESBURG
TO PEORIA TO BLOOMINGTON TO DANVILLE.
I UPDATED THE SNOW GRID TO BETWEEN 1 AND 1.5 INCHES. WITH A NEW
SNOW COVER...TEMPS SHOULD DIP BELOW GUID...PRETTY MUCH IN LINE
WITH THE LOWS WE HAD FORECAST. CLOUDS SHOULD REMAIN ACROSS THE
AREA OVERNIGHT...SO THAT SHOULD HELP KEEP RADIATIONAL COOLING IN
CHECK. THERE IS A CHANCE THAT OUR FAR N CWA MAY SEE A FEW BREAKS
BEFORE SUNRISE...WHICH WILL ALLOW FOR MUCH COLDER LOWS WITH LIGHT
WINDS.
OTHERWISE...THE REMAINDER OF THE FORECAST IS ON TRACK. UPDATED
ZONES AND GRIDS ARE ALREADY AVAILABLE.
SHIMON
&&
.AVIATION...
ISSUED 1150 PM CST SUN JAN 18 2009...FOR THE 06Z TAFS
THE SHORTWAVE SNOW BANDS ARE ALMOST SOUTH OF ALL TAF SITES.
SPI/DEC WILL SEE A BRIEF PERIOD OF SNOW EARLY IN THE TAF
FCST...BUT BY 08Z ALL SNOW SHOULD BE DONE. MVFR CIGS SHOULD BE
LIFTING AT SPI AND DEC SOON. THE OTHER SITES ALL HAVE VFR CIGS OR
NO CIGS AND THEY SHOULD REMAIN THAT WAY UNTIL DURING THE DAY MONDAY.
THE NEXT CLIPPER IS POISED TO QUICKLY DROP SOUTH OUT OF CANADA
MONDAY AFTERNOON...AND PRODUCE A PERIOD OF SNOW MONDAY EVENING IN
CENTRAL IL. THE NEW 00Z GUID IS SHOWING A FEW TENTHS TO A HALF
INCH OF SNOW POSSIBLE. WILL GO WITH A PREVAILING MVFR VIS AND CIG
BEGINNING AT 00Z IN PIA AND PROGRESSING SOUTH DURING THE EVENING.
NORTH WINDS WILL PREVAIL OVER THE NEXT 24 HRS.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 230 PM CST SUN JAN 18 2009
MAIN CONCERNS THIS PACKAGE INCLUDE CHANCES OF LIGHT SNOW THROUGH
MONDAY NIGHT...DEGREE OF WARM UP THROUGH MIDDLE OF THE WEEK...AND
CHANCES OF PCPN TOWARD THE END OF THE WEEK AND THE WEEKEND.
ALL MODELS LOOKED VERY SIMILAR WITH OVERALL PATTERN AND EXPECTED
WEATHER THROUGH NEXT 60-84 HRS. HOWEVER...IN THE EXTENDED TIME
FRAME THERE ARE SOME DIFFERENCES WITH THE RESULTING PATTERN TOWARD
THE END OF THE WEEK. GFS STRONGER WITH A SOUTHERN STREAM SYSTEM
WHILE THE ECMWF IS WEAKER AND KEEPS THE NORTHERN STREAM LITTLE
MORE DOMINATE/STRONGER INTO THE WEEKEND. WITH GFS PRONE TO FLIP-
FLOP THAT FAR OUT AND ECMWF WITH A MORE CONSISTENT TRACK
RECORD...WILL LEAN TOWARD THE ECMWF.
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
THOUGH THE UPPER LEVEL TROUGH WILL BE PUSHING EAST THROUGH THE
PERIOD...MODELS INDICATE THAT TWO MORE WAVES WILL DROP THROUGH
THE CWA NEXT 48HRS. DYNAMICS SHOULD BE SUFFICIENT AND MOISTURE
APPEARS DEEP ENOUGH FOR ALL PCPN TO BE SNOW. FIRST WAVE DROPPING
INTO THE REGION NOW. RADAR WILL OVER-SHOT MOST OF PCPN IN WESTERN
IL BUT IT EVIDENT ON DVN RADAR AT THIS TIME. BELIEVE COVERAGE ON
ILX RADAR WILL INCREASE THROUGH THE EVENING HOURS. BASED ON MODEL
DATA BELIEVE ACCUMULATIONS ARE POSSIBLE TONIGHT ACROSS WHOLE AREA
WITH HIGHER AMOUNTS IN EAST AND SOUTHEAST WHERE SNOW WILL LAST
LONGEST. ACCUMULATIONS OF AROUND ONE HALF INCH LOOKS LIKELY WITH
LESSER AMOUNTS TO THE WEST AND NORTHWEST.
THE SECOND WAVE WILL DROP INTO THE AREA TOMORROW AFTERNOON AND
TOMORROW NIGHT...BEFORE MIDNIGHT. THIS WAVE DOES NOT APPEAR AS
STRONG AS TONIGHT`S AT THIS TIME. HOWEVER...CWA WILL STILL BE IN
CYCLONIC FLOW AND SHOULD BE PLENTY OF MOISTURE TO SQUEEZE OUT SOME
LIGHT SNOW. STRONGEST PART OF THIS WAVE LOOPS TO BE IN THE WEST
PART OF THE CWA SO WILL HAVE HIGHER AMOUNTS THERE.
AGAIN...ACCUMULATIONS LOOK POSSIBLE AND WILL GO WITH AMOUNTS LESS
THAN ONE HALF INCH FOR NOW.
REMAINDER OF THE SHORT TERM SHOULD BE DRY AS HIGH PRESSURE BUILDS
INTO THE REGION, THE UPPER LEVEL TROUGH PUSHES EAST, AND A FLATTER
ZONAL-TYPE PATTERN DEVELOPS OVER THE U.S. THIS WILL LEAD TO DRY
WEATHER OVER THE REGION AND THE POTENTIAL FOR TEMPS TO WARM BACK
UP TO CLOSE TO NORMAL. TEMPS WILL TRICKY DURING THIS PERIOD AND
GRADIENT SHOULD BE TIGHT AS AREAS WITH NO SNOW WILL SEE TEMPS
INCREASE MOST AND QUICKEST MIDDLE OF THE WEEK. AREAS WILL SNOW
WILL LIKELY REMAIN BELOW NORMAL THROUGH WED. GUIDANCE LOOKED OK
TODAY...BUT LOWERED TEMPS FOR WED OVER SNOW FIELD.
LONG TERM...THURSDAY THROUGH SUNDAY
AREA WEATHER WILL CONTINUE TO BE CONTROLLED BY A ZONAL TYPE
PATTERN. TOWARD THE END OF THE WEEK A TWO STREAM PATTERN WILL
SETUP. BELIEVE ECMWF SOLUTION...WITH A WEAKER SOUTHERN STREAM THAN
THE GFS...SEEMS MORE LIKELY WITH VERY COLD AIR STILL BOTTLED UP
NORTH OF THE CONUS. THOUGH SOUTHERN STREAM MAY HAVE A SYSTEM MOVE
FROM SOUTHERN TX INTO THE SOUTHEASTERN US LATE IN THE
PERIOD...BELIEVE ANY AFFECTS OF THIS SYSTEM WILL REMAIN SOUTH OF
THE CWA/STATE. SO WILL KEEP EXTENDED PERIOD DRY AND WAIT TO SEE
WHAT HAPPENS IN LATER MODEL RUNS.
TEMPS WILL REMAIN WARM/NORMAL OR ABOVE INITIALLY FOR THUR BUT A
REINFORCING SHOT OF COLD AIR WILL DROP INTO THE REGION FOR THE
REST OF THE WEEK AND INTO THE WEEKEND. WENT COLDER THAN GUIDANCE
IN THE WEEKEND SINCE GUIDANCE LIKELY TRENDED TOWARD CLIMATOLOGY.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 190256
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
856 PM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 855 PM CST SUN JAN 18 2009
SNOW BANDS HAVE BEEN VIGOROUS AT TIMES THIS EVENING...BUT THE
TRANSIENT NATURE OF THE BANDS HAS KEPT SNOW TOTALS IN ANY ONE AREA
ONLY AROUND AN INCH. SATELLITE AND RADAR TRENDS SHOW THE
ACCUMULATING SNOW WILL ONLY LAST FOR A COUPLE MORE HOURS. AS OF
845 PM...THE BACK EDGE HAS ALREADY REACHED A LINE FROM GALESBURG
TO PEORIA TO BLOOMINGTON TO DANVILLE.
I UPDATED THE SNOW GRID TO BETWEEN 1 AND 1.5 INCHES. WITH A NEW
SNOW COVER...TEMPS SHOULD DIP BELOW GUID...PRETTY MUCH IN LINE
WITH THE LOWS WE HAD FORECAST. CLOUDS SHOULD REMAIN ACROSS THE
AREA OVERNIGHT...SO THAT SHOULD HELP KEEP RADIATIONAL COOLING IN
CHECK. THERE IS A CHANCE THAT OUR FAR N CWA MAY SEE A FEW BREAKS
BEFORE SUNRISE...WHICH WILL ALLOW FOR MUCH COLDER LOWS WITH LIGHT
WINDS.
OTHERWISE...THE REMAINDER OF THE FORECAST IS ON TRACK. UPDATED
ZONES AND GRIDS ARE ALREADY AVAILABLE.
SHIMON
&&
.AVIATION...
ISSUED 529 PM CST SUN JAN 18 2009...FOR THE 00Z TAFS
THE NOSE OF STRONGEST DPVA HAS ARRIVED IN OUR CWA...AND WILL
AFFECT THE TAF SITES FOR ANOTHER 3 TO 5 HOURS. WILL KEEP STEADY
SNOW THIS EVENING AT 4-5SM WITH TEMPOS TO 1-2SM FOR SNOWFALL.
ACCUMS MAY REACH UP TO ONE INCH...BUT MOST AREAS SHOULD REMAIN
DOWN NEAR 1/2 INCH.
CIGS HAVE GENERALLY REMAINED MVFR. BMI WILL MOST LIKELY DROP INTO
IFR...BASED ON PASSED HISTORY WITH LOW CIGS. OTHERWISE...WILL KEEP
TEMPOS FOR CIGS IN THE MVFR CATEGORY AT THE OTHER 4 SITES.
FORECAST SOUNDINGS SHOW LINGERING LOW MOISTURE THROUGH MONDAY
MORNING...AND EVEN BEYOND. CAN NOT RULE OUT SOME PARTIAL CLEARING
MONDAY MORNING...BUT WILL KEEP PREVAILING VFR CIGS IN THE TAFS
THROUGH THE DAY ON MONDAY.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 230 PM CST SUN JAN 18 2009
MAIN CONCERNS THIS PACKAGE INCLUDE CHANCES OF LIGHT SNOW THROUGH
MONDAY NIGHT...DEGREE OF WARM UP THROUGH MIDDLE OF THE WEEK...AND
CHANCES OF PCPN TOWARD THE END OF THE WEEK AND THE WEEKEND.
ALL MODELS LOOKED VERY SIMILAR WITH OVERALL PATTERN AND EXPECTED
WEATHER THROUGH NEXT 60-84 HRS. HOWEVER...IN THE EXTENDED TIME
FRAME THERE ARE SOME DIFFERENCES WITH THE RESULTING PATTERN TOWARD
THE END OF THE WEEK. GFS STRONGER WITH A SOUTHERN STREAM SYSTEM
WHILE THE ECMWF IS WEAKER AND KEEPS THE NORTHERN STREAM LITTLE
MORE DOMINATE/STRONGER INTO THE WEEKEND. WITH GFS PRONE TO FLIP-
FLOP THAT FAR OUT AND ECMWF WITH A MORE CONSISTENT TRACK
RECORD...WILL LEAN TOWARD THE ECMWF.
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
THOUGH THE UPPER LEVEL TROUGH WILL BE PUSHING EAST THROUGH THE
PERIOD...MODELS INDICATE THAT TWO MORE WAVES WILL DROP THROUGH
THE CWA NEXT 48HRS. DYNAMICS SHOULD BE SUFFICIENT AND MOISTURE
APPEARS DEEP ENOUGH FOR ALL PCPN TO BE SNOW. FIRST WAVE DROPPING
INTO THE REGION NOW. RADAR WILL OVER-SHOT MOST OF PCPN IN WESTERN
IL BUT IT EVIDENT ON DVN RADAR AT THIS TIME. BELIEVE COVERAGE ON
ILX RADAR WILL INCREASE THROUGH THE EVENING HOURS. BASED ON MODEL
DATA BELIEVE ACCUMULATIONS ARE POSSIBLE TONIGHT ACROSS WHOLE AREA
WITH HIGHER AMOUNTS IN EAST AND SOUTHEAST WHERE SNOW WILL LAST
LONGEST. ACCUMULATIONS OF AROUND ONE HALF INCH LOOKS LIKELY WITH
LESSER AMOUNTS TO THE WEST AND NORTHWEST.
THE SECOND WAVE WILL DROP INTO THE AREA TOMORROW AFTERNOON AND
TOMORROW NIGHT...BEFORE MIDNIGHT. THIS WAVE DOES NOT APPEAR AS
STRONG AS TONIGHT`S AT THIS TIME. HOWEVER...CWA WILL STILL BE IN
CYCLONIC FLOW AND SHOULD BE PLENTY OF MOISTURE TO SQUEEZE OUT SOME
LIGHT SNOW. STRONGEST PART OF THIS WAVE LOOPS TO BE IN THE WEST
PART OF THE CWA SO WILL HAVE HIGHER AMOUNTS THERE.
AGAIN...ACCUMULATIONS LOOK POSSIBLE AND WILL GO WITH AMOUNTS LESS
THAN ONE HALF INCH FOR NOW.
REMAINDER OF THE SHORT TERM SHOULD BE DRY AS HIGH PRESSURE BUILDS
INTO THE REGION, THE UPPER LEVEL TROUGH PUSHES EAST, AND A FLATTER
ZONAL-TYPE PATTERN DEVELOPS OVER THE U.S. THIS WILL LEAD TO DRY
WEATHER OVER THE REGION AND THE POTENTIAL FOR TEMPS TO WARM BACK
UP TO CLOSE TO NORMAL. TEMPS WILL TRICKY DURING THIS PERIOD AND
GRADIENT SHOULD BE TIGHT AS AREAS WITH NO SNOW WILL SEE TEMPS
INCREASE MOST AND QUICKEST MIDDLE OF THE WEEK. AREAS WILL SNOW
WILL LIKELY REMAIN BELOW NORMAL THROUGH WED. GUIDANCE LOOKED OK
TODAY...BUT LOWERED TEMPS FOR WED OVER SNOW FIELD.
LONG TERM...THURSDAY THROUGH SUNDAY
AREA WEATHER WILL CONTINUE TO BE CONTROLLED BY A ZONAL TYPE
PATTERN. TOWARD THE END OF THE WEEK A TWO STREAM PATTERN WILL
SETUP. BELIEVE ECMWF SOLUTION...WITH A WEAKER SOUTHERN STREAM THAN
THE GFS...SEEMS MORE LIKELY WITH VERY COLD AIR STILL BOTTLED UP
NORTH OF THE CONUS. THOUGH SOUTHERN STREAM MAY HAVE A SYSTEM MOVE
FROM SOUTHERN TX INTO THE SOUTHEASTERN US LATE IN THE
PERIOD...BELIEVE ANY AFFECTS OF THIS SYSTEM WILL REMAIN SOUTH OF
THE CWA/STATE. SO WILL KEEP EXTENDED PERIOD DRY AND WAIT TO SEE
WHAT HAPPENS IN LATER MODEL RUNS.
TEMPS WILL REMAIN WARM/NORMAL OR ABOVE INITIALLY FOR THUR BUT A
REINFORCING SHOT OF COLD AIR WILL DROP INTO THE REGION FOR THE
REST OF THE WEEK AND INTO THE WEEKEND. WENT COLDER THAN GUIDANCE
IN THE WEEKEND SINCE GUIDANCE LIKELY TRENDED TOWARD CLIMATOLOGY.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 182329
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
529 PM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 230 PM CST SUN JAN 18 2009
MAIN CONCERNS THIS PACKAGE INCLUDE CHANCES OF LIGHT SNOW THROUGH
MONDAY NIGHT...DEGREE OF WARM UP THROUGH MIDDLE OF THE WEEK...AND
CHANCES OF PCPN TOWARD THE END OF THE WEEK AND THE WEEKEND.
ALL MODELS LOOKED VERY SIMILAR WITH OVERALL PATTERN AND EXPECTED
WEATHER THROUGH NEXT 60-84 HRS. HOWEVER...IN THE EXTENDED TIME
FRAME THERE ARE SOME DIFFERENCES WITH THE RESULTING PATTERN TOWARD
THE END OF THE WEEK. GFS STRONGER WITH A SOUTHERN STREAM SYSTEM
WHILE THE ECMWF IS WEAKER AND KEEPS THE NORTHERN STREAM LITTLE
MORE DOMINATE/STRONGER INTO THE WEEKEND. WITH GFS PRONE TO FLIP-
FLOP THAT FAR OUT AND ECMWF WITH A MORE CONSISTENT TRACK
RECORD...WILL LEAN TOWARD THE ECMWF.
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
THOUGH THE UPPER LEVEL TROUGH WILL BE PUSHING EAST THROUGH THE
PERIOD...MODELS INDICATE THAT TWO MORE WAVES WILL DROP THROUGH
THE CWA NEXT 48HRS. DYNAMICS SHOULD BE SUFFICIENT AND MOISTURE
APPEARS DEEP ENOUGH FOR ALL PCPN TO BE SNOW. FIRST WAVE DROPPING
INTO THE REGION NOW. RADAR WILL OVER-SHOT MOST OF PCPN IN WESTERN
IL BUT IT EVIDENT ON DVN RADAR AT THIS TIME. BELIEVE COVERAGE ON
ILX RADAR WILL INCREASE THROUGH THE EVENING HOURS. BASED ON MODEL
DATA BELIEVE ACCUMULATIONS ARE POSSIBLE TONIGHT ACROSS WHOLE AREA
WITH HIGHER AMOUNTS IN EAST AND SOUTHEAST WHERE SNOW WILL LAST
LONGEST. ACCUMULATIONS OF AROUND ONE HALF INCH LOOKS LIKELY WITH
LESSER AMOUNTS TO THE WEST AND NORTHWEST.
THE SECOND WAVE WILL DROP INTO THE AREA TOMORROW AFTERNOON AND
TOMORROW NIGHT...BEFORE MIDNIGHT. THIS WAVE DOES NOT APPEAR AS
STRONG AS TONIGHT`S AT THIS TIME. HOWEVER...CWA WILL STILL BE IN
CYCLONIC FLOW AND SHOULD BE PLENTY OF MOISTURE TO SQUEEZE OUT SOME
LIGHT SNOW. STRONGEST PART OF THIS WAVE LOOPS TO BE IN THE WEST
PART OF THE CWA SO WILL HAVE HIGHER AMOUNTS THERE.
AGAIN...ACCUMULATIONS LOOK POSSIBLE AND WILL GO WITH AMOUNTS LESS
THAN ONE HALF INCH FOR NOW.
REMAINDER OF THE SHORT TERM SHOULD BE DRY AS HIGH PRESSURE BUILDS
INTO THE REGION, THE UPPER LEVEL TROUGH PUSHES EAST, AND A FLATTER
ZONAL-TYPE PATTERN DEVELOPS OVER THE U.S. THIS WILL LEAD TO DRY
WEATHER OVER THE REGION AND THE POTENTIAL FOR TEMPS TO WARM BACK
UP TO CLOSE TO NORMAL. TEMPS WILL TRICKY DURING THIS PERIOD AND
GRADIENT SHOULD BE TIGHT AS AREAS WITH NO SNOW WILL SEE TEMPS
INCREASE MOST AND QUICKEST MIDDLE OF THE WEEK. AREAS WILL SNOW
WILL LIKELY REMAIN BELOW NORMAL THROUGH WED. GUIDANCE LOOKED OK
TODAY...BUT LOWERED TEMPS FOR WED OVER SNOW FIELD.
LONG TERM...THURSDAY THROUGH SUNDAY
AREA WEATHER WILL CONTINUE TO BE CONTROLLED BY A ZONAL TYPE
PATTERN. TOWARD THE END OF THE WEEK A TWO STREAM PATTERN WILL
SETUP. BELIEVE ECMWF SOLUTION...WITH A WEAKER SOUTHERN STREAM THAN
THE GFS...SEEMS MORE LIKELY WITH VERY COLD AIR STILL BOTTLED UP
NORTH OF THE CONUS. THOUGH SOUTHERN STREAM MAY HAVE A SYSTEM MOVE
FROM SOUTHERN TX INTO THE SOUTHEASTERN US LATE IN THE
PERIOD...BELIEVE ANY AFFECTS OF THIS SYSTEM WILL REMAIN SOUTH OF
THE CWA/STATE. SO WILL KEEP EXTENDED PERIOD DRY AND WAIT TO SEE
WHAT HAPPENS IN LATER MODEL RUNS.
TEMPS WILL REMAIN WARM/NORMAL OR ABOVE INITIALLY FOR THUR BUT A
REINFORCING SHOT OF COLD AIR WILL DROP INTO THE REGION FOR THE
REST OF THE WEEK AND INTO THE WEEKEND. WENT COLDER THAN GUIDANCE
IN THE WEEKEND SINCE GUIDANCE LIKELY TRENDED TOWARD CLIMATOLOGY.
AUTEN
&&
.AVIATION...
ISSUED 529 PM CST SUN JAN 18 2009...FOR THE 00Z TAFS
THE NOSE OF STRONGEST DPVA HAS ARRIVED IN OUR CWA...AND WILL
AFFECT THE TAF SITES FOR ANOTHER 3 TO 5 HOURS. WILL KEEP STEADY
SNOW THIS EVENING AT 4-5SM WITH TEMPOS TO 1-2SM FOR SNOWFALL.
ACCUMS MAY REACH UP TO ONE INCH...BUT MOST AREAS SHOULD REMAIN
DOWN NEAR 1/2 INCH.
CIGS HAVE GENERALLY REMAINED MVFR. BMI WILL MOST LIKELY DROP INTO
IFR...BASED ON PASSED HISTORY WITH LOW CIGS. OTHERWISE...WILL KEEP
TEMPOS FOR CIGS IN THE MVFR CATEGORY AT THE OTHER 4 SITES.
FORECAST SOUNDINGS SHOW LINGERING LOW MOISTURE THROUGH MONDAY
MORNING...AND EVEN BEYOND. CAN NOT RULE OUT SOME PARTIAL CLEARING
MONDAY MORNING...BUT WILL KEEP PREVAILING VFR CIGS IN THE TAFS
THROUGH THE DAY ON MONDAY.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 182030
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
230 PM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 230 PM CST SUN JAN 18 2009
MAIN CONCERNS THIS PACKAGE INCLUDE CHANCES OF LIGHT SNOW THROUGH
MONDAY NIGHT...DEGREE OF WARM UP THROUGH MIDDLE OF THE WEEK...AND
CHANCES OF PCPN TOWARD THE END OF THE WEEK AND THE WEEKEND.
ALL MODELS LOOKED VERY SIMILAR WITH OVERALL PATTERN AND EXPECTED
WEATHER THROUGH NEXT 60-84 HRS. HOWEVER...IN THE EXTENDED TIME
FRAME THERE ARE SOME DIFFERENCES WITH THE RESULTING PATTERN TOWARD
THE END OF THE WEEK. GFS STRONGER WITH A SOUTHERN STREAM SYSTEM
WHILE THE ECMWF IS WEAKER AND KEEPS THE NORTHERN STREAM LITTLE
MORE DOMINATE/STRONGER INTO THE WEEKEND. WITH GFS PRONE TO FLIP-
FLOP THAT FAR OUT AND ECMWF WITH A MORE CONSISTENT TRACK
RECORD...WILL LEAN TOWARD THE ECMWF.
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
THOUGH THE UPPER LEVEL TROUGH WILL BE PUSHING EAST THROUGH THE
PERIOD...MODELS INDICATE THAT TWO MORE WAVES WILL DROP THROUGH
THE CWA NEXT 48HRS. DYNAMICS SHOULD BE SUFFICIENT AND MOISTURE
APPEARS DEEP ENOUGH FOR ALL PCPN TO BE SNOW. FIRST WAVE DROPPING
INTO THE REGION NOW. RADAR WILL OVER-SHOT MOST OF PCPN IN WESTERN
IL BUT IT EVIDENT ON DVN RADAR AT THIS TIME. BELIEVE COVERAGE ON
ILX RADAR WILL INCREASE THROUGH THE EVENING HOURS. BASED ON MODEL
DATA BELIEVE ACCUMULATIONS ARE POSSIBLE TONIGHT ACROSS WHOLE AREA
WITH HIGHER AMOUNTS IN EAST AND SOUTHEAST WHERE SNOW WILL LAST
LONGEST. ACCUMULATIONS OF AROUND ONE HALF INCH LOOKS LIKELY WITH
LESSER AMOUNTS TO THE WEST AND NORTHWEST.
THE SECOND WAVE WILL DROP INTO THE AREA TOMORROW AFTERNOON AND
TOMORROW NIGHT...BEFORE MIDNIGHT. THIS WAVE DOES NOT APPEAR AS
STRONG AS TONIGHT`S AT THIS TIME. HOWEVER...CWA WILL STILL BE IN
CYCLONIC FLOW AND SHOULD BE PLENTY OF MOISTURE TO SQUEEZE OUT SOME
LIGHT SNOW. STRONGEST PART OF THIS WAVE LOOPS TO BE IN THE WEST
PART OF THE CWA SO WILL HAVE HIGHER AMOUNTS THERE.
AGAIN...ACCUMULATIONS LOOK POSSIBLE AND WILL GO WITH AMOUNTS LESS
THAN ONE HALF INCH FOR NOW.
REMAINDER OF THE SHORT TERM SHOULD BE DRY AS HIGH PRESSURE BUILDS
INTO THE REGION, THE UPPER LEVEL TROUGH PUSHES EAST, AND A FLATTER
ZONAL-TYPE PATTERN DEVELOPS OVER THE U.S. THIS WILL LEAD TO DRY
WEATHER OVER THE REGION AND THE POTENTIAL FOR TEMPS TO WARM BACK
UP TO CLOSE TO NORMAL. TEMPS WILL TRICKY DURING THIS PERIOD AND
GRADIENT SHOULD BE TIGHT AS AREAS WITH NO SNOW WILL SEE TEMPS
INCREASE MOST AND QUICKEST MIDDLE OF THE WEEK. AREAS WILL SNOW
WILL LIKELY REMAIN BELOW NORMAL THROUGH WED. GUIDANCE LOOKED OK
TODAY...BUT LOWERED TEMPS FOR WED OVER SNOW FIELD.
LONG TERM...THURSDAY THROUGH SUNDAY
AREA WEATHER WILL CONTINUE TO BE CONTROLLED BY A ZONAL TYPE
PATTERN. TOWARD THE END OF THE WEEK A TWO STREAM PATTERN WILL
SETUP. BELIEVE ECMWF SOLUTION...WITH A WEAKER SOUTHERN STREAM THAN
THE GFS...SEEMS MORE LIKELY WITH VERY COLD AIR STILL BOTTLED UP
NORTH OF THE CONUS. THOUGH SOUTHERN STREAM MAY HAVE A SYSTEM MOVE
FROM SOUTHERN TX INTO THE SOUTHEASTERN US LATE IN THE
PERIOD...BELIEVE ANY AFFECTS OF THIS SYSTEM WILL REMAIN SOUTH OF
THE CWA/STATE. SO WILL KEEP EXTENDED PERIOD DRY AND WAIT TO SEE
WHAT HAPPENS IN LATER MODEL RUNS.
TEMPS WILL REMAIN WARM/NORMAL OR ABOVE INITIALLY FOR THUR BUT A
REINFORCING SHOT OF COLD AIR WILL DROP INTO THE REGION FOR THE
REST OF THE WEEK AND INTO THE WEEKEND. WENT COLDER THAN GUIDANCE
IN THE WEEKEND SINCE GUIDANCE LIKELY TRENDED TOWARD CLIMATOLOGY.
AUTEN
&&
.AVIATION...
ISSUED 1155 AM CST SUN JAN 18 2009
LARGE VERTICALLY STACKED LOW PRESSURE WAS OVER CENTRAL LAKE HURON
WITH 1003 MB SURFACE LOW PRESSURE AND 520 DM 500 MB LOW. LOW
PRESSURE FORECAST TO MOVE TOWARD LAKE ONTARIO BY 18Z/MON WHILE
WEAK HIGH PRESSURE MOVES INTO THE MO VALLEY BY MON AFTERNOON. DEEP
UPPER LEVEL TROF WILL REMAIN OVER THE EASTERN STATES. A SHORT WAVE
OVER NE MN...NW WI AND WESTERN LAKE SUPERIOR WILL DIVE SOUTHWARD
ACROSS CENTRAL IL THIS EVENING AND BRING SCATTERED LIGHT SNOW
SHOWERS TO THE CENTRAL IL TERMINALS. MVFR CLOUDS SW OF I-74 WITH
BMI STILL CLEAR (PIA JUST WENT BROKEN 2300 FT). BMI SHOULD
DEVELOP MVFR CEILINGS TOO IN THE NEXT HOUR OR TWO...AND MVFR
CEILINGS WILL PREVAIL ACROSS CENTRAL IL THROUGH TONIGHT. CEILINGS
SHOULD LIFT TO VFR JUST ABOVE 3K FT AFTER 15Z/SUN AND MAY EVEN
SCATTERED OUT LATER SUNDAY MORNING ESPECIALLY PIA AND BMI LIKE
WHAT HAPPENED THIS MORNING IN THE WAKE OF A SHORT WAVE. NW WINDS
NEAR 10 KTS WILL BECOME NNW AND INCREASE TO NEAR 15 KTS BY
OVERNIGHT AND COULD GUST NEAR 20 KTS. NNW WINDS DECREASE TO 10 TO
15 KTS AFTER 15Z/SAT AS WEAK HIGH PRESSURE BREAKS OFF FROM STRONG
HIGH PRESSURE OVER THE ROCKIES AND MOVES INTO THE MO VALLEY BY
SUNDAY AFTERNOON.
HUETTL
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 181755
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1155 AM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 1045 AM CST SUN JAN 18 2009
UPDATING THE FORECAST TO ELEVATE HIGHS A DEGREE OR TWO INTO THE
LOW TO MID 30S IN THE SW COUNTIES WHILE KEEPING MUCH COOLER HIGHS
IN THE MID 20S OVER THE DEEPER SNOW COVER IN THE NE. SCATTERED
LIGHT SNOW SHOWERS WILL CONTINUE THIS AFTERNOON AND BE MORE COMMON
SW OF I-74. LIGHTER NW WINDS OF 5 TO 15 MPH TODAY.
16Z/10 AM SURFACE MAP SHOWS 1004 MB LOW PRESSURE OVER CENTRAL LAKE
HURON WITH ITS COLD FRONT EXTENDING THROUGH SE OH...NORTHERN KY
INTO SW IL ALONG A QUINCY TO FLORA LINE. AN AREA OF LIGHT SNOW
SHOWERS SPREAD SE ACROSS THE SW COUNTIES THIS MORNING AND JUST
EXITING SE OF LAWRENCEVILLE BY 1030 AM WITH A SHORT WAVE NEARING
THE OHIO RIVER. SNOWFALL AMOUNTS GENERALLY A DUSTING WITH LOCAL
QUARTER TO HALF INCH AMOUNTS. THERE WERE ALSO REPORTS OF A HOUR OR
TWO OF FREEZING DRIZZLE OVER PARTS OF SANGAMON AND CHRISTIAN
COUNTIES CAUSING SOME SLICK SURFACES SINCE TEMPS BELOW FREEZING.
LOW CLOUDS COVERED CENTRAL/SW IL SW OF I-74 WHILE A LARGE CLEAR
AREA NE OF I-74 OVER NE THIRD OF IL. TEMPS RANGED FROM THE MID
TEENS NE OF I-74 TO AROUND 30F FROM JACKSONVILLE AND ROBINSON SW.
DEWPOINTS RANGED FROM SINGLE DIGITS NE OF I-74 TO 25 TO 30F SW
AREAS CLOSER TO THE FRONT. ALOFT A STRONG 520 DM 500 MB LOW WAS
OVER THE SURFACE LOW OVER CENTRAL LAKE HURON WITH LARGE/DEEP UPPER
LEVEL TROF OVER THE EASTERN U.S. WHILE STRONG UPPER LEVEL RIDGE
OVER WESTERN NORTH AMERICA.
SHORT RANGE MODELS SHOW ANOTHER SHORT WAVE OVER NW MN ARROWHEAD...
WESTERN LAKE SUPERIOR AND NW WI DIVING SOUTH ACROSS
NORTHERN/CENTRAL IL LATE THIS AFTERNOON AND EVENING. THIS TO BRING
MORE SCATTERED LIGHT SNOW SHOWERS TO THE AREA AND DIMINISH OVERNIGHT.
LOW CLOUDS SHOULD RETURN TO AREAS NE OF I-74 DURING NEXT FEW HOURS
WITH STEEP LAPSE RATES. HIGHS RANGE FROM MID 20S FROM I-74 NE OVER
DEEPER SNOW COVER TO THE LOW TO MID 30S SW AREAS.
HUETTL
&&
.AVIATION...
ISSUED 1155 AM CST SUN JAN 18 2009
LARGE VERTICALLY STACKED LOW PRESSURE WAS OVER CENTRAL LAKE HURON
WITH 1003 MB SURFACE LOW PRESSURE AND 520 DM 500 MB LOW. LOW
PRESSURE FORECAST TO MOVE TOWARD LAKE ONTARIO BY 18Z/MON WHILE
WEAK HIGH PRESSURE MOVES INTO THE MO VALLEY BY MON AFTERNOON. DEEP
UPPER LEVEL TROF WILL REMAIN OVER THE EASTERN STATES. A SHORT WAVE
OVER NE MN...NW WI AND WESTERN LAKE SUPERIOR WILL DIVE SOUTHWARD
ACROSS CENTRAL IL THIS EVENING AND BRING SCATTERED LIGHT SNOW
SHOWERS TO THE CENTRAL IL TERMINALS. MVFR CLOUDS SW OF I-74 WITH
BMI STILL CLEAR (PIA JUST WENT BROKEN 2300 FT). BMI SHOULD
DEVELOP MVFR CEILINGS TOO IN THE NEXT HOUR OR TWO...AND MVFR
CEILINGS WILL PREVAIL ACROSS CENTRAL IL THROUGH TONIGHT. CEILINGS
SHOULD LIFT TO VFR JUST ABOVE 3K FT AFTER 15Z/SUN AND MAY EVEN
SCATTERED OUT LATER SUNDAY MORNING ESPECIALLY PIA AND BMI LIKE
WHAT HAPPENED THIS MORNING IN THE WAKE OF A SHORT WAVE. NW WINDS
NEAR 10 KTS WILL BECOME NNW AND INCREASE TO NEAR 15 KTS BY
OVERNIGHT AND COULD GUST NEAR 20 KTS. NNW WINDS DECREASE TO 10 TO
15 KTS AFTER 15Z/SAT AS WEAK HIGH PRESSURE BREAKS OFF FROM STRONG
HIGH PRESSURE OVER THE ROCKIES AND MOVES INTO THE MO VALLEY BY
SUNDAY AFTERNOON.
HUETTL
&&
.PREV DISCUSSION...
ISSUED 307 AM CST SUN JAN 18 2009
FZDZ FROM THE OVERNIGHT SEEMS TO HAVE CLEARED UP A BIT ON THE
RADAR...THOUGH ANOTHER WAVE OF PRECIP IS DIVING THROUGH IA AND
HEADED THIS WAY. GENERAL RIDGING OVER THE WEST COAST...WITH A
MAJOR TROF OVER THE ERN HALF OF THE CONUS. MAJOR ISSUES FOR THE
FORECAST OVER THE NEXT 5 DAYS IS THE HANDLING OF THE SHORTWAVE
TODAY...AND ANOTHER TOMORROW NIGHT...AS WELL AS THE ASSOCIATED
PRECIP. BEYOND THAT...THERE ARE INCONSISTENCIES WITH THE MODELS
BEYOND DAY 5 IN THE HANDLING OF THE LONGER TERM. FOR NOW...WILL
USE A BLEND FOR THE GRIDS.
SHORT TERM...TODAY AND MONDAY...
NORTH/NORTHWESTERLY FLOW CONTINUES FROM CENTRAL CANADA...KEEPING
ALOFT A BIT BUSY WITH A SERIES OF SHORTWAVES...EASILY DISCERNIBLE
ON WV SATELLITE IMAGERY THIS MORNING. A QUICK PASS OF A WAVE
EXPECTED TODAY AS SOME SNOW OVER IA EARLY THIS MORNING MAKES ITS
WAY ACROSS SWRN AND CENTRAL ILLINOIS. WAVE IS MOVING FAST ENOUGH
THAT NOT MUCH IN THE WAY OF ACCUMULATION IS EXPECTED WITH THIS
SYSTEM...UNDER AN INCH. SNOW EXPECTED TO END BY MIDNIGHT AND MUCH
OF THE DAY TOMORROW TO BE DRY...THOUGH A BIT COLDER WITH MORE
NWRLY FLOW. TOMORROW LATE AFTERNOON ANOTHER WAVE QUICKLY RUSHES
THROUGH THE MIDWEST...WITH ANOTHER LIGHT DUSTING OF SNOW AFTER
NOON AND BEFORE MIDNIGHT.
LONG TERM...TUESDAY THROUGH THURSDAY...
GUIDANCE IS TRENDING WARMER THROUGH THE MED RANGE...AS THE MODELS
TRY TO SHIFT TO A MORE ZONAL PATTERN. AND BEYOND MIDWEEK THE
ENSEMBLE FORECASTS SHIFT THE NAO TO A NEGATIVE PHASE WHICH
SUPPORTS A WEAKER SUBTROPICAL RIDGE AND ICELANDIC LOW...ALLOWING
THE FLOW TO STRAIGHTEN OUT A BIT...AND TEMPERATURES TO MODERATE. BUT THE
ECMWF IS JUST A TOUCH COLDER FOR A BIT LONGER...AND DRIER. FOR
NOW...THE EXTENDED IS MORE A REFLECTION OF THE ECMWF...DRY ON
FRIDAY...WHEREAS THE GFS BRINGS ANOTHER SYSTEM OUT OF
COLORADO...RIGHT THROUGH THE MIDWEST.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 181645
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1045 AM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 1045 AM CST SUN JAN 18 2009
UPDATING THE FORECAST TO ELEVATE HIGHS A DEGREE OR TWO INTO THE
LOW TO MID 30S IN THE SW COUNTIES WHILE KEEPING MUCH COOLER HIGHS
IN THE MID 20S OVER THE DEEPER SNOW COVER IN THE NE. SCATTERED
LIGHT SNOW SHOWERS WILL CONTINUE THIS AFTERNOON AND BE MORE COMMON
SW OF I-74. LIGHTER NW WINDS OF 5 TO 15 MPH TODAY.
16Z/10 AM SURFACE MAP SHOWS 1004 MB LOW PRESSURE OVER CENTRAL LAKE
HURON WITH ITS COLD FRONT EXTENDING THROUGH SE OH...NORTHERN KY
INTO SW IL ALONG A QUINCY TO FLORA LINE. AN AREA OF LIGHT SNOW
SHOWERS SPREAD SE ACROSS THE SW COUNTIES THIS MORNING AND JUST
EXITING SE OF LAWRENCEVILLE BY 1030 AM WITH A SHORT WAVE NEARING
THE OHIO RIVER. SNOWFALL AMOUNTS GENERALLY A DUSTING WITH LOCAL
QUARTER TO HALF INCH AMOUNTS. THERE WERE ALSO REPORTS OF A HOUR OR
TWO OF FREEZING DRIZZLE OVER PARTS OF SANGAMON AND CHRISTIAN
COUNTIES CAUSING SOME SLICK SURFACES SINCE TEMPS BELOW FREEZING.
LOW CLOUDS COVERED CENTRAL/SW IL SW OF I-74 WHILE A LARGE CLEAR
AREA NE OF I-74 OVER NE THIRD OF IL. TEMPS RANGED FROM THE MID
TEENS NE OF I-74 TO AROUND 30F FROM JACKSONVILLE AND ROBINSON SW.
DEWPOINTS RANGED FROM SINGLE DIGITS NE OF I-74 TO 25 TO 30F SW
AREAS CLOSER TO THE FRONT. ALOFT A STRONG 520 DM 500 MB LOW WAS
OVER THE SURFACE LOW OVER CENTRAL LAKE HURON WITH LARGE/DEEP UPPER
LEVEL TROF OVER THE EASTERN U.S. WHILE STRONG UPPER LEVEL RIDGE
OVER WESTERN NORTH AMERICA.
SHORT RANGE MODELS SHOW ANOTHER SHORT WAVE OVER NW MN ARROWHEAD...
WESTERN LAKE SUPERIOR AND NW WI DIVING SOUTH ACROSS
NORTHERN/CENTRAL IL LATE THIS AFTERNOON AND EVENING. THIS TO BRING
MORE SCATTERED LIGHT SNOW SHOWERS TO THE AREA AND DIMINISH OVERNIGHT.
LOW CLOUDS SHOULD RETURN TO AREAS NE OF I-74 DURING NEXT FEW HOURS
WITH STEEP LAPSE RATES. HIGHS RANGE FROM MID 20S FROM I-74 NE OVER
DEEPER SNOW COVER TO THE LOW TO MID 30S SW AREAS.
HUETTL
&&
.AVIATION...
ISSUED 554 AM CST SUN JAN 18 2009
MVFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH THE 12Z
TAF PERIOD. LOW PRESSURE OVER THE GREAT LAKES WILL SLOWLY DRIFT
EAST THROUGH THE PERIOD. ADDITIONAL UPPER LEVEL DISTURBANCES
DIVING DOWN THE BACK SIDE OF THE DEPARTING AREA OF LOW PRESSURE
WILL KEEP LOW CLOUDS AND PERIODS OF SNOW SHOWERS/FLURRIES IN THE
AREA. MOST OF THE SNOW SHOWERS WILL BE QUITE LIGHT...WITH LATE
THIS AFTERNOON/EARLY THIS EVENING THE MOST FAVORED TIME FOR
SNOWFALL. SKIES MAY BEGIN TO SCATTER OUT AFTER 06Z TONIGHT...BUT
CONFIDENCE IS TOO LOW TO INCLUDE THIS IN THE TAFS AT THIS TIME.
BAK
&&
.PREV DISCUSSION...
ISSUED 307 AM CST SUN JAN 18 2009
FZDZ FROM THE OVERNIGHT SEEMS TO HAVE CLEARED UP A BIT ON THE
RADAR...THOUGH ANOTHER WAVE OF PRECIP IS DIVING THROUGH IA AND
HEADED THIS WAY. GENERAL RIDGING OVER THE WEST COAST...WITH A
MAJOR TROF OVER THE ERN HALF OF THE CONUS. MAJOR ISSUES FOR THE
FORECAST OVER THE NEXT 5 DAYS IS THE HANDLING OF THE SHORTWAVE
TODAY...AND ANOTHER TOMORROW NIGHT...AS WELL AS THE ASSOCIATED
PRECIP. BEYOND THAT...THERE ARE INCONSISTENCIES WITH THE MODELS
BEYOND DAY 5 IN THE HANDLING OF THE LONGER TERM. FOR NOW...WILL
USE A BLEND FOR THE GRIDS.
SHORT TERM...TODAY AND MONDAY...
NORTH/NORTHWESTERLY FLOW CONTINUES FROM CENTRAL CANADA...KEEPING
ALOFT A BIT BUSY WITH A SERIES OF SHORTWAVES...EASILY DISCERNIBLE
ON WV SATELLITE IMAGERY THIS MORNING. A QUICK PASS OF A WAVE
EXPECTED TODAY AS SOME SNOW OVER IA EARLY THIS MORNING MAKES ITS
WAY ACROSS SWRN AND CENTRAL ILLINOIS. WAVE IS MOVING FAST ENOUGH
THAT NOT MUCH IN THE WAY OF ACCUMULATION IS EXPECTED WITH THIS
SYSTEM...UNDER AN INCH. SNOW EXPECTED TO END BY MIDNIGHT AND MUCH
OF THE DAY TOMORROW TO BE DRY...THOUGH A BIT COLDER WITH MORE
NWRLY FLOW. TOMORROW LATE AFTERNOON ANOTHER WAVE QUICKLY RUSHES
THROUGH THE MIDWEST...WITH ANOTHER LIGHT DUSTING OF SNOW AFTER
NOON AND BEFORE MIDNIGHT.
LONG TERM...TUESDAY THROUGH THURSDAY...
GUIDANCE IS TRENDING WARMER THROUGH THE MED RANGE...AS THE MODELS
TRY TO SHIFT TO A MORE ZONAL PATTERN. AND BEYOND MIDWEEK THE
ENSEMBLE FORECASTS SHIFT THE NAO TO A NEGATIVE PHASE WHICH
SUPPORTS A WEAKER SUBTROPICAL RIDGE AND ICELANDIC LOW...ALLOWING
THE FLOW TO STRAIGHTEN OUT A BIT...AND TEMPERATURES TO MODERATE. BUT THE
ECMWF IS JUST A TOUCH COLDER FOR A BIT LONGER...AND DRIER. FOR
NOW...THE EXTENDED IS MORE A REFLECTION OF THE ECMWF...DRY ON
FRIDAY...WHEREAS THE GFS BRINGS ANOTHER SYSTEM OUT OF
COLORADO...RIGHT THROUGH THE MIDWEST.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 181154
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
554 AM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 307 AM CST SUN JAN 18 2009
FZDZ FROM THE OVERNIGHT SEEMS TO HAVE CLEARED UP A BIT ON THE
RADAR...THOUGH ANOTHER WAVE OF PRECIP IS DIVING THROUGH IA AND
HEADED THIS WAY. GENERAL RIDGING OVER THE WEST COAST...WITH A
MAJOR TROF OVER THE ERN HALF OF THE CONUS. MAJOR ISSUES FOR THE
FORECAST OVER THE NEXT 5 DAYS IS THE HANDLING OF THE SHORTWAVE
TODAY...AND ANOTHER TOMORROW NIGHT...AS WELL AS THE ASSOCIATED
PRECIP. BEYOND THAT...THERE ARE INCONSISTENCIES WITH THE MODELS
BEYOND DAY 5 IN THE HANDLING OF THE LONGER TERM. FOR NOW...WILL
USE A BLEND FOR THE GRIDS.
SHORT TERM...TODAY AND TOMORROW...
NORTH/NORTHWESTERLY FLOW CONTINUES FROM CENTRAL CANADA...KEEPING
ALOFT A BIT BUSY WITH A SERIES OF SHORTWAVES...EASILY DISCERNIBLE
ON WV SATELLITE IMAGERY THIS MORNING. A QUICK PASS OF A WAVE
EXPECTED TODAY AS SOME SNOW OVER IA EARLY THIS MORNING MAKES ITS
WAY ACROSS SWRN AND CENTRAL ILLINOIS. WAVE IS MOVING FAST ENOUGH
THAT NOT MUCH IN THE WAY OF ACCUMULATION IS EXPECTED WITH THIS
SYSTEM...UNDER AN INCH. SNOW EXPECTED TO END BY MIDNIGHT AND MUCH
OF THE DAY TOMORROW TO BE DRY...THOUGH A BIT COLDER WITH MORE NWRLY
FLOW. TOMORROW LATE AFTERNOON ANOTHER WAVE QUICKLY RUSHES THROUGH THE
MIDWEST...WITH ANOTHER LIGHT DUSTING OF SNOW AFTER NOON AND BEFORE
MIDNIGHT.
LONG TERM...TUESDAY THROUGH THURSDAY...
GUIDANCE IS TRENDING WARMER THROUGH THE MED RANGE...AS THE MODELS
TRY TO SHIFT TO A MORE ZONAL PATTERN. AND BEYOND MIDWEEK THE
ENSEMBLE FORECASTS SHIFT THE NAO TO A NEGATIVE PHASE WHICH
SUPPORTS A WEAKER SUBTROPICAL RIDGE AND ICELANDIC LOW...ALLOWING
THE FLOW TO STRAIGHTEN OUT A BIT...AND TEMPERATURES TO MODERATE. BUT THE
ECMWF IS JUST A TOUCH COLDER FOR A BIT LONGER...AND DRIER. FOR
NOW...THE EXTENDED IS MORE A REFLECTION OF THE ECMWF...DRY ON
FRIDAY...WHEREAS THE GFS BRINGS ANOTHER SYSTEM OUT OF
COLORADO...RIGHT THROUGH THE MIDWEST.
HJS
&&
.AVIATION...
ISSUED 554 AM CST SUN JAN 18 2009
MVFR CONDITIONS WILL PREVAIL ACROSS THE TERMINALS THROUGH THE 12Z
TAF PERIOD. LOW PRESSURE OVER THE GREAT LAKES WILL SLOWLY DRIFT
EAST THROUGH THE PERIOD. ADDITIONAL UPPER LEVEL DISTURBANCES
DIVING DOWN THE BACK SIDE OF THE DEPARTING AREA OF LOW PRESSURE
WILL KEEP LOW CLOUDS AND PERIODS OF SNOW SHOWERS/FLURRIES IN THE
AREA. MOST OF THE SNOW SHOWERS WILL BE QUITE LIGHT...WITH LATE
THIS AFTERNOON/EARLY THIS EVENING THE MOST FAVORED TIME FOR
SNOWFALL. SKIES MAY BEGIN TO SCATTER OUT AFTER 06Z TONIGHT...BUT
CONFIDENCE IS TOO LOW TO INCLUDE THIS IN THE TAFS AT THIS TIME.
BAK
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 180929
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
329 AM CST SUN JAN 18 2009
.DISCUSSION...
ISSUED 307 AM CST SUN JAN 18 2009
FZDZ FROM THE OVERNIGHT SEEMS TO HAVE CLEARED UP A BIT ON THE
RADAR...THOUGH ANOTHER WAVE OF PRECIP IS DIVING THROUGH IA AND
HEADED THIS WAY. GENERAL RIDGING OVER THE WEST COAST...WITH A
MAJOR TROF OVER THE ERN HALF OF THE CONUS. MAJOR ISSUES FOR THE
FORECAST OVER THE NEXT 5 DAYS IS THE HANDLING OF THE SHORTWAVE
TODAY...AND ANOTHER TOMORROW NIGHT...AS WELL AS THE ASSOCIATED
PRECIP. BEYOND THAT...THERE ARE INCONSISTENCIES WITH THE MODELS
BEYOND DAY 5 IN THE HANDLING OF THE LONGER TERM. FOR NOW...WILL
USE A BLEND FOR THE GRIDS.
SHORT TERM...TODAY AND TOMORROW...
NORTH/NORTHWESTERLY FLOW CONTINUES FROM CENTRAL CANADA...KEEPING
ALOFT A BIT BUSY WITH A SERIES OF SHORTWAVES...EASILY DISCERNIBLE
ON WV SATELLITE IMAGERY THIS MORNING. A QUICK PASS OF A WAVE
EXPECTED TODAY AS SOME SNOW OVER IA EARLY THIS MORNING MAKES ITS
WAY ACROSS SWRN AND CENTRAL ILLINOIS. WAVE IS MOVING FAST ENOUGH
THAT NOT MUCH IN THE WAY OF ACCUMULATION IS EXPECTED WITH THIS
SYSTEM...UNDER AN INCH. SNOW EXPECTED TO END BY MIDNIGHT AND MUCH
OF THE DAY TOMORROW TO BE DRY...THOUGH A BIT COLDER WITH MORE NWRLY
FLOW. TOMORROW LATE AFTERNOON ANOTHER WAVE QUICKLY RUSHES THROUGH THE
MIDWEST...WITH ANOTHER LIGHT DUSTING OF SNOW AFTER NOON AND BEFORE
MIDNIGHT.
LONG TERM...TUESDAY THROUGH THURSDAY...
GUIDANCE IS TRENDING WARMER THROUGH THE MED RANGE...AS THE MODELS
TRY TO SHIFT TO A MORE ZONAL PATTERN. AND BEYOND MIDWEEK THE
ENSEMBLE FORECASTS SHIFT THE NAO TO A NEGATIVE PHASE WHICH
SUPPORTS A WEAKER SUBTROPICAL RIDGE AND ICELANDIC LOW...ALLOWING
THE FLOW TO STRAIGHTEN OUT A BIT...AND TEMPERATURES TO MODERATE. BUT THE
ECMWF IS JUST A TOUCH COLDER FOR A BIT LONGER...AND DRIER. FOR
NOW...THE EXTENDED IS MORE A REFLECTION OF THE ECMWF...DRY ON
FRIDAY...WHEREAS THE GFS BRINGS ANOTHER SYSTEM OUT OF
COLORADO...RIGHT THROUGH THE MIDWEST.
HJS
&&
.AVIATION...
ISSUED 1129 PM CST SAT JAN 17 2009...FOR THE 06Z TAFS
IT APPEARS THE FZDZ MAY BE ADVANCING EASTWARD AS MIDNIGHT
APPROACHES. WE NO LONGER HAVE ANY FZDZ HERE IN LINCOLN AND CMI IS
REPORTING FZ PRECIP AGAIN. MOST SITES IN THE WESTERN HALF OF THE
CWA ARE NOW REPORTING VERY LIGHT -SN. THE SECONDARY TROUGH IS
POISED IN N IL TO DROP SOUTH INTO OUR CWA BY 12Z SUNDAY. A MORE
NORTHERLY COMPONENT IS EXPECTED IN THE POST TROUGH WINDS...ALONG
WITH AN INCREASE IN MID LVL RH. THIS WILL HELP KEEP PRECIP AS SNOW
ON SUNDAY...INSTEAD OF FREEZING DRIZZLE.
THE UPPER FLOW IS NEARLY MERIDIONAL /N TO S/ WITH A JET MAX SURGING
SOUTH ACROSS W MN AND W IOWA. THIS FEATURE WILL PLAY A ROLL IN THE
LIGHT MEASURABLE SNOW FOR CENTRAL IL ON SUNDAY. THE 00Z MODELS ARE
STILL DEPICTING SNOW FOR US...WITH THE HEAVIER BAND OF AROUND ONE
INCH FOR THE SW HALF OF THE CWA...SOUTHWEST OF RUSHVILLE TO
MATTOON. A HALF INCH OR LESS IS EXPECTED FOR PIA TO BMI.
CIGS WILL REMAIN MVFR FOR MUCH OF THE NEXT 24 HRS...BASED ON THE
LONG WAVE TROUGH REMAINING ACROSS THE WESTERN GREAT LAKES AND
HEARTLAND AREA. CMI DIPPED TO IFR AT 04Z...AND SOME PERIODS OF IFR
CIGS MAY OCCUR AT THE OTHER SITES AS WELL...BUT TIMING IS VERY
DIFFICULT...SO WILL NOT INCLUDE TEMPOS FOR THAT.
VIS HAS BEEN OK SO FAR THIS EVENING...WITH BMI THE ONLY SITE TO GO
IFR IN SNOW. RADAR RETURNS HAVE BEEN WEAKENING THE LAST HOUR...SO
WILL NOT TEMPO LOW VIS. WILL GO WITH STEADY LIGHT SNOW FOR MID
MORN INTO THE AFTERNOON ON SUNDAY...AS THE WEAK CLIPPER PASSES BY
TO THE SW OF OUR CWA.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 180530
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1130 PM CST SAT JAN 17 2009
.DISCUSSION...
ISSUED 850 PM CST SAT JAN 17 2009
A COMBINATION OF FREEZING DRIZZLE AND FLURRIES HAS DEVELOPED
ACROSS THE NORTHERN TWO THIRDS OF THE CWA. TEMPS ARE ABOVE
FREEZING FROM I-70 AND SOUTH...SO JUST DRIZZLE THERE...BUT THE
GROUND MAY STILL BE COLD ENOUGH FOR A SHORT PERIOD OF FREEZING ON
THE GROUND. RUC SOUNDINGS SHOW NO SATURATION IN AIR BELOW
-10C...WHERE ICE CRYSTALS ARE MORE LIKELY TO DEVELOP AND FALL INTO
THE LOW MOIST LAYER. RH LEVELS ARE STILL NEAR 70 PERCENT IN THE
COLD LAYER ALOFT...AN SOME FLURRIES ARE IN FACT DEVELOPING ALONG
WITH THE FREEZING DRIZZLE.
AFTER MIDNIGHT...THE SOUNDINGS SHOW HIGHER RH LEVELS IN THE COLD
LAYER ALOFT AND A BETTER CHANCE OF ICE CRYSTALS ALOFT. HAVE UPDATED
THE EVENING GRIDS TO ADD FZDZ IN THE N CWA THIS EVENING. ALSO ADDED
BLOWING SNOW FROM PIA AND NORTH...WHERE WE HAD REPORTS OF DRIFTS
AFFECTING SOME ROADS.
A SECONDARY TROF IS DROPPING S TOWARD C IL. IT REACHED SW IOWA AND
N IL BY 02Z. THIS SECOND TROF WILL USHER IN SLIGHTLY HIGHER RH
LEVELS AND A CHANCE OF LIGHT SNOW OR FLURRIES THE REST OF THE
NIGHT.
TEMPS ARE HOLDING RELATIVELY STEADY SO FAR THIS EVENING...BUT
UPSTREAM CAA SHOULD PROGRESS INTO OUR AREA BEHIND THE NEXT TROF.
THINGS LOOKS ON TRACK FOR A QUICK SHOT OF SNOW ON SUNDAY...AS A
WEAK CLIPPER PASSES BY JUST TO THE SW OF OUR CWA. WE MAY SEE AS
MUCH AS ONE INCH OF SNOW FROM SPI TO EFFINGHAM...WITH TAPERING
AMOUNTS TOWARD LINCOLN/PIA/BMI. PIA MAY SEE UP TO A HALF INCH
BEFORE SUNDAY EVENING. WE CURRENTLY HAVE 30 POPS FOR
SUNDAY...MAINLY FOR THE SCATTERED NATURE OF THE SHOWERS...NOT ALL
AREAS WILL SEE SNOW ACCUMS. WILL SEE WHAT THE 00Z MODELS
INDICATE...FOR POSSIBLE ADJUSTMENTS TO POPS ON SUNDAY.
UPDATED ZONES AND GRIDS ARE ALREADY AVAILABLE FOR TONIGHT.
SHIMON
&&
.AVIATION...
ISSUED 1129 PM CST SAT JAN 17 2009...FOR THE 06Z TAFS
IT APPEARS THE FZDZ MAY BE ADVANCING EASTWARD AS MIDNIGHT
APPROACHES. WE NO LONGER HAVE ANY FZDZ HERE IN LINCOLN AND CMI IS
REPORTING FZ PRECIP AGAIN. MOST SITES IN THE WESTERN HALF OF THE
CWA ARE NOW REPORTING VERY LIGHT -SN. THE SECONDARY TROUGH IS
POISED IN N IL TO DROP SOUTH INTO OUR CWA BY 12Z SUNDAY. A MORE
NORTHERLY COMPONENT IS EXPECTED IN THE POST TROUGH WINDS...ALONG
WITH AN INCREASE IN MID LVL RH. THIS WILL HELP KEEP PRECIP AS SNOW
ON SUNDAY...INSTEAD OF FREEZING DRIZZLE.
THE UPPER FLOW IS NEARLY MERIDIONAL /N TO S/ WITH A JET MAX SURGING
SOUTH ACROSS W MN AND W IOWA. THIS FEATURE WILL PLAY A ROLL IN THE
LIGHT MEASURABLE SNOW FOR CENTRAL IL ON SUNDAY. THE 00Z MODELS ARE
STILL DEPICTING SNOW FOR US...WITH THE HEAVIER BAND OF AROUND ONE
INCH FOR THE SW HALF OF THE CWA...SOUTHWEST OF RUSHVILLE TO
MATTOON. A HALF INCH OR LESS IS EXPECTED FOR PIA TO BMI.
CIGS WILL REMAIN MVFR FOR MUCH OF THE NEXT 24 HRS...BASED ON THE
LONG WAVE TROUGH REMAINING ACROSS THE WESTERN GREAT LAKES AND
HEARTLAND AREA. CMI DIPPED TO IFR AT 04Z...AND SOME PERIODS OF IFR
CIGS MAY OCCUR AT THE OTHER SITES AS WELL...BUT TIMING IS VERY
DIFFICULT...SO WILL NOT INCLUDE TEMPOS FOR THAT.
VIS HAS BEEN OK SO FAR THIS EVENING...WITH BMI THE ONLY SITE TO GO
IFR IN SNOW. RADAR RETURNS HAVE BEEN WEAKENING THE LAST HOUR...SO
WILL NOT TEMPO LOW VIS. WILL GO WITH STEADY LIGHT SNOW FOR MID
MORN INTO THE AFTERNOON ON SUNDAY...AS THE WEAK CLIPPER PASSES BY
TO THE SW OF OUR CWA.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 253 PM CST SAT JAN 17 2009
ONLY REAL CONCERN THIS PACKAGE WILL BE INVOLVING CHC OF SNOW AND
FLURRIES THROUGH MONDAY NIGHT. MODELS IN GOOD AGREEMENT DURING THE
SHORT TERM PERIODS WITH CONTINUED CYCLONIC FLOW OVER THE REGION
SLOWLY MOVING EAST LATE IN THE PERIOD. ONLY DIFFERENCES SEEN IN
THE SHORT TERM IS WITH THE AMOUNT OF QPF/SNOW EXPECTED.
IN THE LONG TERM...THE MODELS ARE IN GOOD AGREEMENT WITH THE
FORECASTED TRANSITION OF THE UPPER LEVEL PATTERN BECOMING MORE
ZONAL.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
ONE SHORT WAVE/FRONT IS MOVING THROUGH THE CWA THIS AFTERNOON AND
EVENING AND IS BRINGING LOTS OF CLOUD COVER TO THE AREA. CAA IN
THE LOW LEVELS MOVES IN AFTER THE TROUGH MOVES THROUGH. THOUGH
TEMPS WILL NOT GET AS COLD AS THE PAST TWO DAYS...WITH THE
INCREASED MOISTURE...AM EXPECTING FLURRIES OR LIGHT SNOW TONIGHT.
LIGHT RETURNS SHOWING UP ON MOSAIC RADAR LOOPS SO WILL CONTINUE
MENTION OF FLURRIES IN FORECAST FOR TONIGHT. MODELS THEN SHOW
LITTLE BIT STRONGER WAVE COMING DOWN TOMORROW AND BRINGING DEEPER
MOISTURE INTO THE REGION. THIS WILL BRING BETTER CHC OF PCPN TO
THE CWA FOR SUNDAY AND SUNDAY NIGHT. THEREFORE HAVE INCREASED POPS
TO 30PCT 0F LIGHT SNOW FOR TOMORROW AND INTO TOMORROW NIGHT IN
THE SOUTHEAST CWA. HAVE ALSO INCREASED SNOWFALL TOTALS DURING THIS
PERIOD TO AROUND 1/2-1 INCH POSSIBLE.
A FINAL WEAKER TROUGH ROTATES THROUGH MON AND BRINGS THE FINAL
SHOT OF FLURRIES TO THE CWA FOR MON AND MON NIGHT. NO REAL
ACCUMULATIONS EXPECTED WITH THIS SYSTEM. BY TUESDAY...THE UPPER
LEVEL TROUGH WILL HAVE PUSHED EAST OF THE AREA AND THE SFC PATTERN
ACROSS THE CWA WILL START TO BECOME MORE ANTI-CYCLONIC. THIS WILL
BRING DRY WEATHER TO THE CWA AND THE BEGINNING OF A SLIGHT WARMING
TREND INTO THE EXTENDED.
TEMPS WILL REMAIN BELOW NORMAL THROUGH THE PERIOD BUT SOME AREAS
SHOULD SEE ABOVE FREEZING TEMPS BY TUESDAY. GUIDANCE TEMPS DO NOT
LOOK TOO BAD BUT DID TREND SLIGHTLY LOWER WITH FORECAST TEMPS.
LONG TERM...WEDNESDAY THROUGH SATURDAY
ECMWF MODEL VERY CONSISTENT IN SHOWING THE PATTERN BECOMING MORE
ZONAL BY LATER HALF OF THE WEEK AND INTO THE WEEKEND. THIS WILL
BRING DRY WEATHER TO THE REGION FOR THE ENTIRE EXTENDED PERIOD.
TEMPS WILL ALSO BE WARMER WED AND THURSDAY...HOWEVER A DRY FRONT
WILL DROP INTO THE REGION EARLY FRIDAY AND BRING THE RETURN OF
BELOW NORMAL TEMPS FOR FRI AND SAT. NO PCPN IS EXPECTED AS THE
BEST DYNAMICS WILL BE WELL NORTH OF THE AREA AND IN THE SOUTHERN
PLAINS.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 180250
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
850 PM CST SAT JAN 17 2009
.DISCUSSION...
ISSUED 850 PM CST SAT JAN 17 2009
A COMBINATION OF FREEZING DRIZZLE AND FLURRIES HAS DEVELOPED
ACROSS THE NORTHERN TWO THIRDS OF THE CWA. TEMPS ARE ABOVE
FREEZING FROM I-70 AND SOUTH...SO JUST DRIZZLE THERE...BUT THE
GROUND MAY STILL BE COLD ENOUGH FOR A SHORT PERIOD OF FREEZING ON
THE GROUND. RUC SOUNDINGS SHOW NO SATURATION IN AIR BELOW
-10C...WHERE ICE CRYSTALS ARE MORE LIKELY TO DEVELOP AND FALL INTO
THE LOW MOIST LAYER. RH LEVELS ARE STILL NEAR 70 PERCENT IN THE
COLD LAYER ALOFT...AN SOME FLURRIES ARE IN FACT DEVELOPING ALONG
WITH THE FREEZING DRIZZLE.
AFTER MIDNIGHT...THE SOUNDINGS SHOW HIGHER RH LEVELS IN THE COLD
LAYER ALOFT AND A BETTER CHANCE OF ICE CRYSTALS ALOFT. HAVE UPDATED
THE EVENING GRIDS TO ADD FZDZ IN THE N CWA THIS EVENING. ALSO ADDED
BLOWING SNOW FROM PIA AND NORTH...WHERE WE HAD REPORTS OF DRIFTS
AFFECTING SOME ROADS.
A SECONDARY TROF IS DROPPING S TOWARD C IL. IT REACHED SW IOWA AND
N IL BY 02Z. THIS SECOND TROF WILL USHER IN SLIGHTLY HIGHER RH
LEVELS AND A CHANCE OF LIGHT SNOW OR FLURRIES THE REST OF THE
NIGHT.
TEMPS ARE HOLDING RELATIVELY STEADY SO FAR THIS EVENING...BUT
UPSTREAM CAA SHOULD PROGRESS INTO OUR AREA BEHIND THE NEXT TROF.
THINGS LOOKS ON TRACK FOR A QUICK SHOT OF SNOW ON SUNDAY...AS A
WEAK CLIPPER PASSES BY JUST TO THE SW OF OUR CWA. WE MAY SEE AS
MUCH AS ONE INCH OF SNOW FROM SPI TO EFFINGHAM...WITH TAPERING
AMOUNTS TOWARD LINCOLN/PIA/BMI. PIA MAY SEE UP TO A HALF INCH
BEFORE SUNDAY EVENING. WE CURRENTLY HAVE 30 POPS FOR
SUNDAY...MAINLY FOR THE SCATTERED NATURE OF THE SHOWERS...NOT ALL
AREAS WILL SEE SNOW ACCUMS. WILL SEE WHAT THE 00Z MODELS
INDICATE...FOR POSSIBLE ADJUSTMENTS TO POPS ON SUNDAY.
UPDATED ZONES AND GRIDS ARE ALREADY AVAILABLE FOR TONIGHT.
SHIMON
&&
.AVIATION...
ISSUED 535 PM CST SAT JAN 17 2009...FOR THE 00Z TAFS
LOW CLOUDS AND FLURRIES WILL LINGER THROUGH THE NIGHT ACROSS C
IL...AS AN H5 SHORTWAVE PASS THROUGH THE AREA. THE INITIAL SURFACE
TROUGH IS ALREADY INTO INDIANA...BUT A TRAILING TROUGH IS POISED
TO DROP INTO C IL OVER THE NEXT FEW HOURS.
THAT SECOND TROF WILL HELP KEEP CIGS MVFR OVERNIGHT. VIS SHOULD
NOT BE MUCH OF A PROBLEM. BLSN MIGHT ACTUALLY DO MORE TO REDUCE
VIS THAN ANY SNOW SHOWERS THIS EVENING...UNTIL THE WINDS DECREASE
BY MIDNIGHT. PIA AND BMI WILL HAVE THE BEST CHANCES FOR ANY
MEASURABLE SNOW. WILL PUT 4SM -SN THERE...BUT NOT LOWER THAN THAT.
SNOW SHOWERS SHOULD DIMINISH SUN MORNING.
A NARROW BAND OF SNOW IS EXPECTED TO DEVELOP SUNDAY EVENING...FOR
OUR SW TAFS OF SPI AND DEC. THAT TIMING IS JUST OUTSIDE THE WINDOW
OF THESE TAFS...BUT THE MIDNIGHT ISSUANCE WILL NEED TO ADDRESS
THAT NEXT SHORTWAVE.
SHIMON
&&
.PREV DISCUSSION...
ISSUED 253 PM CST SAT JAN 17 2009
ONLY REAL CONCERN THIS PACKAGE WILL BE INVOLVING CHC OF SNOW AND
FLURRIES THROUGH MONDAY NIGHT. MODELS IN GOOD AGREEMENT DURING THE
SHORT TERM PERIODS WITH CONTINUED CYCLONIC FLOW OVER THE REGION
SLOWLY MOVING EAST LATE IN THE PERIOD. ONLY DIFFERENCES SEEN IN
THE SHORT TERM IS WITH THE AMOUNT OF QPF/SNOW EXPECTED.
IN THE LONG TERM...THE MODELS ARE IN GOOD AGREEMENT WITH THE
FORECASTED TRANSITION OF THE UPPER LEVEL PATTERN BECOMING MORE
ZONAL.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
ONE SHORT WAVE/FRONT IS MOVING THROUGH THE CWA THIS AFTERNOON AND
EVENING AND IS BRINGING LOTS OF CLOUD COVER TO THE AREA. CAA IN
THE LOW LEVELS MOVES IN AFTER THE TROUGH MOVES THROUGH. THOUGH
TEMPS WILL NOT GET AS COLD AS THE PAST TWO DAYS...WITH THE
INCREASED MOISTURE...AM EXPECTING FLURRIES OR LIGHT SNOW TONIGHT.
LIGHT RETURNS SHOWING UP ON MOSAIC RADAR LOOPS SO WILL CONTINUE
MENTION OF FLURRIES IN FORECAST FOR TONIGHT. MODELS THEN SHOW
LITTLE BIT STRONGER WAVE COMING DOWN TOMORROW AND BRINGING DEEPER
MOISTURE INTO THE REGION. THIS WILL BRING BETTER CHC OF PCPN TO
THE CWA FOR SUNDAY AND SUNDAY NIGHT. THEREFORE HAVE INCREASED POPS
TO 30PCT 0F LIGHT SNOW FOR TOMORROW AND INTO TOMORROW NIGHT IN
THE SOUTHEAST CWA. HAVE ALSO INCREASED SNOWFALL TOTALS DURING THIS
PERIOD TO AROUND 1/2-1 INCH POSSIBLE.
A FINAL WEAKER TROUGH ROTATES THROUGH MON AND BRINGS THE FINAL
SHOT OF FLURRIES TO THE CWA FOR MON AND MON NIGHT. NO REAL
ACCUMULATIONS EXPECTED WITH THIS SYSTEM. BY TUESDAY...THE UPPER
LEVEL TROUGH WILL HAVE PUSHED EAST OF THE AREA AND THE SFC PATTERN
ACROSS THE CWA WILL START TO BECOME MORE ANTI-CYCLONIC. THIS WILL
BRING DRY WEATHER TO THE CWA AND THE BEGINNING OF A SLIGHT WARMING
TREND INTO THE EXTENDED.
TEMPS WILL REMAIN BELOW NORMAL THROUGH THE PERIOD BUT SOME AREAS
SHOULD SEE ABOVE FREEZING TEMPS BY TUESDAY. GUIDANCE TEMPS DO NOT
LOOK TOO BAD BUT DID TREND SLIGHTLY LOWER WITH FORECAST TEMPS.
LONG TERM...WEDNESDAY THROUGH SATURDAY
ECMWF MODEL VERY CONSISTENT IN SHOWING THE PATTERN BECOMING MORE
ZONAL BY LATER HALF OF THE WEEK AND INTO THE WEEKEND. THIS WILL
BRING DRY WEATHER TO THE REGION FOR THE ENTIRE EXTENDED PERIOD.
TEMPS WILL ALSO BE WARMER WED AND THURSDAY...HOWEVER A DRY FRONT
WILL DROP INTO THE REGION EARLY FRIDAY AND BRING THE RETURN OF
BELOW NORMAL TEMPS FOR FRI AND SAT. NO PCPN IS EXPECTED AS THE
BEST DYNAMICS WILL BE WELL NORTH OF THE AREA AND IN THE SOUTHERN
PLAINS.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 172336
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
536 PM CST SAT JAN 17 2009
.DISCUSSION...
ISSUED 253 PM CST SAT JAN 17 2009
ONLY REAL CONCERN THIS PACKAGE WILL BE INVOLVING CHC OF SNOW AND
FLURRIES THROUGH MONDAY NIGHT. MODELS IN GOOD AGREEMENT DURING THE
SHORT TERM PERIODS WITH CONTINUED CYCLONIC FLOW OVER THE REGION
SLOWLY MOVING EAST LATE IN THE PERIOD. ONLY DIFFERENCES SEEN IN
THE SHORT TERM IS WITH THE AMOUNT OF QPF/SNOW EXPECTED.
IN THE LONG TERM...THE MODELS ARE IN GOOD AGREEMENT WITH THE
FORECASTED TRANSITION OF THE UPPER LEVEL PATTERN BECOMING MORE
ZONAL.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
ONE SHORT WAVE/FRONT IS MOVING THROUGH THE CWA THIS AFTERNOON AND
EVENING AND IS BRINGING LOTS OF CLOUD COVER TO THE AREA. CAA IN
THE LOW LEVELS MOVES IN AFTER THE TROUGH MOVES THROUGH. THOUGH
TEMPS WILL NOT GET AS COLD AS THE PAST TWO DAYS...WITH THE
INCREASED MOISTURE...AM EXPECTING FLURRIES OR LIGHT SNOW TONIGHT.
LIGHT RETURNS SHOWING UP ON MOSAIC RADAR LOOPS SO WILL CONTINUE
MENTION OF FLURRIES IN FORECAST FOR TONIGHT. MODELS THEN SHOW
LITTLE BIT STRONGER WAVE COMING DOWN TOMORROW AND BRINGING DEEPER
MOISTURE INTO THE REGION. THIS WILL BRING BETTER CHC OF PCPN TO
THE CWA FOR SUNDAY AND SUNDAY NIGHT. THEREFORE HAVE INCREASED POPS
TO 30PCT 0F LIGHT SNOW FOR TOMORROW AND INTO TOMORROW NIGHT IN
THE SOUTHEAST CWA. HAVE ALSO INCREASED SNOWFALL TOTALS DURING THIS
PERIOD TO AROUND 1/2-1 INCH POSSIBLE.
A FINAL WEAKER TROUGH ROTATES THROUGH MON AND BRINGS THE FINAL
SHOT OF FLURRIES TO THE CWA FOR MON AND MON NIGHT. NO REAL
ACCUMULATIONS EXPECTED WITH THIS SYSTEM. BY TUESDAY...THE UPPER
LEVEL TROUGH WILL HAVE PUSHED EAST OF THE AREA AND THE SFC PATTERN
ACROSS THE CWA WILL START TO BECOME MORE ANTI-CYCLONIC. THIS WILL
BRING DRY WEATHER TO THE CWA AND THE BEGINNING OF A SLIGHT WARMING
TREND INTO THE EXTENDED.
TEMPS WILL REMAIN BELOW NORMAL THROUGH THE PERIOD BUT SOME AREAS
SHOULD SEE ABOVE FREEZING TEMPS BY TUESDAY. GUIDANCE TEMPS DO NOT
LOOK TOO BAD BUT DID TREND SLIGHTLY LOWER WITH FORECAST TEMPS.
LONG TERM...WEDNESDAY THROUGH SATURDAY
ECMWF MODEL VERY CONSISTENT IN SHOWING THE PATTERN BECOMING MORE
ZONAL BY LATER HALF OF THE WEEK AND INTO THE WEEKEND. THIS WILL
BRING DRY WEATHER TO THE REGION FOR THE ENTIRE EXTENDED PERIOD.
TEMPS WILL ALSO BE WARMER WED AND THURSDAY...HOWEVER A DRY FRONT
WILL DROP INTO THE REGION EARLY FRIDAY AND BRING THE RETURN OF
BELOW NORMAL TEMPS FOR FRI AND SAT. NO PCPN IS EXPECTED AS THE
BEST DYNAMICS WILL BE WELL NORTH OF THE AREA AND IN THE SOUTHERN
PLAINS.
AUTEN
&&
.AVIATION...
ISSUED 535 PM CST SAT JAN 17 2009...FOR THE 00Z TAFS
LOW CLOUDS AND FLURRIES WILL LINGER THROUGH THE NIGHT ACROSS C
IL...AS AN H5 SHORTWAVE PASS THROUGH THE AREA. THE INITIAL SURFACE
TROUGH IS ALREADY INTO INDIANA...BUT A TRAILING TROUGH IS POISED
TO DROP INTO C IL OVER THE NEXT FEW HOURS.
THAT SECOND TROF WILL HELP KEEP CIGS MVFR OVERNIGHT. VIS SHOULD
NOT BE MUCH OF A PROBLEM. BLSN MIGHT ACTUALLY DO MORE TO REDUCE
VIS THAN ANY SNOW SHOWERS THIS EVENING...UNTIL THE WINDS DECREASE
BY MIDNIGHT. PIA AND BMI WILL HAVE THE BEST CHANCES FOR ANY
MEASURABLE SNOW. WILL PUT 4SM -SN THERE...BUT NOT LOWER THAN THAT.
SNOW SHOWERS SHOULD DIMINISH SUN MORNING.
A NARROW BAND OF SNOW IS EXPECTED TO DEVELOP SUNDAY EVENING...FOR
OUR SW TAFS OF SPI AND DEC. THAT TIMING IS JUST OUTSIDE THE WINDOW
OF THESE TAFS...BUT THE MIDNIGHT ISSUANCE WILL NEED TO ADDRESS
THAT NEXT SHORTWAVE.
SHIMON
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 172056 CCA
AFDILX
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE LINCOLN IL
256 PM CST SAT JAN 17 2009
.DISCUSSION...
ISSUED 253 PM CST SAT JAN 17 2009
ONLY REAL CONCERN THIS PACKAGE WILL BE INVOLVING CHC OF SNOW AND
FLURRIES THROUGH MONDAY NIGHT. MODELS IN GOOD AGREEMENT DURING THE
SHORT TERM PERIODS WITH CONTINUED CYCLONIC FLOW OVER THE REGION
SLOWLY MOVING EAST LATE IN THE PERIOD. ONLY DIFFERENCES SEEN IN
THE SHORT TERM IS WITH THE AMOUNT OF QPF/SNOW EXPECTED.
IN THE LONG TERM...THE MODELS ARE IN GOOD AGREEMENT WITH THE
FORECASTED TRANSITION OF THE UPPER LEVEL PATTERN BECOMING MORE
ZONAL.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
ONE SHORT WAVE/FRONT IS MOVING THROUGH THE CWA THIS AFTERNOON AND
EVENING AND IS BRINGING LOTS OF CLOUD COVER TO THE AREA. CAA IN
THE LOW LEVELS MOVES IN AFTER THE TROUGH MOVES THROUGH. THOUGH
TEMPS WILL NOT GET AS COLD AS THE PAST TWO DAYS...WITH THE
INCREASED MOISTURE...AM EXPECTING FLURRIES OR LIGHT SNOW TONIGHT.
LIGHT RETURNS SHOWING UP ON MOSAIC RADAR LOOPS SO WILL CONTINUE
MENTION OF FLURRIES IN FORECAST FOR TONIGHT. MODELS THEN SHOW
LITTLE BIT STRONGER WAVE COMING DOWN TOMORROW AND BRINGING DEEPER
MOISTURE INTO THE REGION. THIS WILL BRING BETTER CHC OF PCPN TO
THE CWA FOR SUNDAY AND SUNDAY NIGHT. THEREFORE HAVE INCREASED POPS
TO 30PCT 0F LIGHT SNOW FOR TOMORROW AND INTO TOMORROW NIGHT IN
THE SOUTHEAST CWA. HAVE ALSO INCREASED SNOWFALL TOTALS DURING THIS
PERIOD TO AROUND 1/2-1 INCH POSSIBLE.
A FINAL WEAKER TROUGH ROTATES THROUGH MON AND BRINGS THE FINAL
SHOT OF FLURRIES TO THE CWA FOR MON AND MON NIGHT. NO REAL
ACCUMULATIONS EXPECTED WITH THIS SYSTEM. BY TUESDAY...THE UPPER
LEVEL TROUGH WILL HAVE PUSHED EAST OF THE AREA AND THE SFC PATTERN
ACROSS THE CWA WILL START TO BECOME MORE ANTI-CYCLONIC. THIS WILL
BRING DRY WEATHER TO THE CWA AND THE BEGINNING OF A SLIGHT WARMING
TREND INTO THE EXTENDED.
TEMPS WILL REMAIN BELOW NORMAL THROUGH THE PERIOD BUT SOME AREAS
SHOULD SEE ABOVE FREEZING TEMPS BY TUESDAY. GUIDANCE TEMPS DO NOT
LOOK TOO BAD BUT DID TREND SLIGHTLY LOWER WITH FORECAST TEMPS.
LONG TERM...WEDNESDAY THROUGH SATURDAY
ECMWF MODEL VERY CONSISTENT IN SHOWING THE PATTERN BECOMING MORE
ZONAL BY LATER HALF OF THE WEEK AND INTO THE WEEKEND. THIS WILL
BRING DRY WEATHER TO THE REGION FOR THE ENTIRE EXTENDED PERIOD.
TEMPS WILL ALSO BE WARMER WED AND THURSDAY...HOWEVER A DRY FRONT
WILL DROP INTO THE REGION EARLY FRIDAY AND BRING THE RETURN OF
BELOW NORMAL TEMPS FOR FRI AND SAT. NO PCPN IS EXPECTED AS THE
BEST DYNAMICS WILL BE WELL NORTH OF THE AREA AND IN THE SOUTHERN
PLAINS.
AUTEN
&&
.AVIATION...
ISSUED 1150 AM CST SAT JAN 17 2009
OVERCAST MVFR CEILINGS NW OF THE IL RIVER AT PIA WILL SPREAD SE
TO TO I-55 AT BMI AND SPI FROM 19Z-20Z AND DEC AND CMI FROM 20Z-21Z.
OVERCAST MVFR CEILINGS WILL LIKELY CONTINUE THROUGH SUNDAY MORNING.
THIS DUE TO LOW PRESSURE OVER WESTERN LOWER MI THAT MOVES ACROSS
THE GREAT LAKES WITH UPPER LEVEL TROF DIGGING OVER THE OHIO VALLEY.
CONTINUED CHANCE OF FLURRIES FROM MID AFTERNOON INTO TONIGHT AND
COULD LINGER INTO SUNDAY. BRUNT OF LIGHT SNOW AND VISIBILITY
RESTRICTIONS WILL BE NE OF I-74 THROUGH SUNDAY MORNING. STRONG SSW
WINDS 15 TO 20 KTS WITH GUSTS OF 25 TO 30 KTS WILL TURN WEST
BEHIND A COLD FRONT THAT IS ALONG THE IA/IL BORDER AND RACES SE
ACROSS CENTRAL IL DURING THIS AFTERNOON AND DIMINISHING TO 10 TO 15
KTS TONIGHT AS THE WINDS TURN NW BY 06Z/MIDNIGHT TONIGHT.
HUETTL
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 172053
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
253 PM CST SAT JAN 17 2009
.DISCUSSION...
ISSUED 2531 PM CST SAT JAN 17 2009
ONLY REAL CONCERN THIS PACKAGE WILL BE INVOLVING CHC OF SNOW AND
FLURRIES THROUGH MONDAY NIGHT. MODELS IN GOOD AGREEMENT DURING THE
SHORT TERM PERIODS WITH CONTINUED CYCLONIC FLOW OVER THE REGION
SLOWLY MOVING EAST LATE IN THE PERIOD. ONLY DIFFERENCES SEEN IN
THE SHORT TERM IS WITH THE AMOUNT OF QPF/SNOW EXPECTED.
IN THE LONG TERM...THE MODELS ARE IN GOOD AGREEMENT WITH THE
FORECASTED TRANSITION OF THE UPPER LEVEL PATTERN BECOMING MORE
ZONAL.
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
ONE SHORT WAVE/FRONT IS MOVING THROUGH THE CWA THIS AFTERNOON AND
EVENING AND IS BRINGING LOTS OF CLOUD COVER TO THE AREA. CAA IN
THE LOW LEVELS MOVES IN AFTER THE TROUGH MOVES THROUGH. THOUGH
TEMPS WILL NOT GET AS COLD AS THE PAST TWO DAYS...WITH THE
INCREASED MOISTURE...AM EXPECTING FLURRIES OR LIGHT SNOW TONIGHT.
LIGHT RETURNS SHOWING UP ON MOSAIC RADAR LOOPS SO WILL CONTINUE
MENTION OF FLURRIES IN FORECAST FOR TONIGHT. MODELS THEN SHOW
LITTLE BIT STRONGER WAVE COMING DOWN TOMORROW AND BRINGING DEEPER
MOISTURE INTO THE REGION. THIS WILL BRING BETTER CHC OF PCPN TO
THE CWA FOR SUNDAY AND SUNDAY NIGHT. THEREFORE HAVE INCREASED POPS
TO 30PCT 0F LIGHT SNOW FOR TOMORROW AND INTO TOMORROW NIGHT IN
THE SOUTHEAST CWA. HAVE ALSO INCREASED SNOWFALL TOTALS DURING THIS
PERIOD TO AROUND 1/2-1 INCH POSSIBLE.
A FINAL WEAKER TROUGH ROTATES THROUGH MON AND BRINGS THE FINAL
SHOT OF FLURRIES TO THE CWA FOR MON AND MON NIGHT. NO REAL
ACCUMULATIONS EXPECTED WITH THIS SYSTEM. BY TUESDAY...THE UPPER
LEVEL TROUGH WILL HAVE PUSHED EAST OF THE AREA AND THE SFC PATTERN
ACROSS THE CWA WILL START TO BECOME MORE ANTI-CYCLONIC. THIS WILL
BRING DRY WEATHER TO THE CWA AND THE BEGINNING OF A SLIGHT WARMING
TREND INTO THE EXTENDED.
TEMPS WILL REMAIN BELOW NORMAL THROUGH THE PERIOD BUT SOME AREAS
SHOULD SEE ABOVE FREEZING TEMPS BY TUESDAY. GUIDANCE TEMPS DO NOT
LOOK TOO BAD BUT DID TREND SLIGHTLY LOWER WITH FORECAST TEMPS.
LONG TERM...WEDNESDAY THROUGH SATURDAY
ECMWF MODEL VERY CONSISTENT IN SHOWING THE PATTERN BECOMING MORE
ZONAL BY LATER HALF OF THE WEEK AND INTO THE WEEKEND. THIS WILL
BRING DRY WEATHER TO THE REGION FOR THE ENTIRE EXTENDED PERIOD.
TEMPS WILL ALSO BE WARMER WED AND THURSDAY...HOWEVER A DRY FRONT
WILL DROP INTO THE REGION EARLY FRIDAY AND BRING THE RETURN OF
BELOW NORMAL TEMPS FOR FRI AND SAT. NO PCPN IS EXPECTED AS THE
BEST DYNAMICS WILL BE WELL NORTH OF THE AREA AND IN THE SOUTHERN
PLAINS.
AUTEN
&&
.AVIATION...
ISSUED 1150 AM CST SAT JAN 17 2009
OVERCAST MVFR CEILINGS NW OF THE IL RIVER AT PIA WILL SPREAD SE
TO TO I-55 AT BMI AND SPI FROM 19Z-20Z AND DEC AND CMI FROM 20Z-21Z.
OVERCAST MVFR CEILINGS WILL LIKELY CONTINUE THROUGH SUNDAY MORNING.
THIS DUE TO LOW PRESSURE OVER WESTERN LOWER MI THAT MOVES ACROSS
THE GREAT LAKES WITH UPPER LEVEL TROF DIGGING OVER THE OHIO VALLEY.
CONTINUED CHANCE OF FLURRIES FROM MID AFTERNOON INTO TONIGHT AND
COULD LINGER INTO SUNDAY. BRUNT OF LIGHT SNOW AND VISIBILITY
RESTRICTIONS WILL BE NE OF I-74 THROUGH SUNDAY MORNING. STRONG SSW
WINDS 15 TO 20 KTS WITH GUSTS OF 25 TO 30 KTS WILL TURN WEST
BEHIND A COLD FRONT THAT IS ALONG THE IA/IL BORDER AND RACES SE
ACROSS CENTRAL IL DURING THIS AFTERNOON AND DIMINISHING TO 10 TO 15
KTS TONIGHT AS THE WINDS TURN NW BY 06Z/MIDNIGHT TONIGHT.
HUETTL
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
000
FXUS63 KILX 171756
AFDILX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1156 AM CST SAT JAN 17 2009
.DISCUSSION...
ISSUED 1045 AM CST SAT JAN 17 2009
ISSUED A SHORT TERM FORECAST TODAY FOR BLOWING AND DRIFTING SNOW
ACROSS EAST TO WEST ROADS MAINLY IN OPEN RURAL DUE TO SOUTH WINDS
15 TO 25 MPH AND GUSTS OF 25 TO 35 MPH. OTHERWISE WARMED HIGHS A
DEGREE OR TWO ESPECIALLY AROUND GALESBURG WHICH IS CURRENTLY 25F.
ALSO ADJUSTING SKY COVER WITH MORE SUNSHINE LATE THIS MORNING AND
THEN CLOUDING BACK UP DURING THE AFTERNOON FROM NW TO SE WITH
CHANCE OF FLURRIES NORTH.
16Z/10 AM SURFACE MAP SHOWS 1005 MB LOW PRESSURE OVER WESTERN LAKE
SUPERIOR WITH ITS COLD FRONT EXTENDING INTO CENTRAL IA AND NW MO.
STRONG SOUTH WINDS 15 TO 25 MPH AND GUSTS OF 25 TO 35 MPH AHEAD OF
THIS FRONT OVER IL. TEMPERATURES ELEVATED INTO THE 20S EXCEPT 18F
AT BLOOMINGTON AND 19F IN PEORIA WHERE WIND CHILLS AROUND ZERO.
A DRY WEDGE HAS WORKED INTO CENTRAL AND SOUTHERN IL WHERE CLOUDS
TEMPORARILY CLEARED BY MID MORNING.
SHORT RANGE MODELS SIMILAR IN MOVING LOW PRESSURE SE OVER CENTRAL
LAKE MI BY 00Z/6 PM AND DRIVING COLD FRONT SE THROUGH CENTRAL IL
DURING THIS AFTERNOON. STRONG SSW WINDS TO TURN WEST BEHIND COLD
FRONT AND LOW CLOUDS TO INCREASE FROM NW TO SE DURING THE
AFTERNOON. BRUNT OF LIGHT SNOW TO PASS NE OF CENTRAL IL AND JUST
HAVE CHANCE OF FLURRIES FROM I-74 NE THIS AFTERNOON. HIGHS TO
RANGE FROM THE UPPER 20S TO NEAR 30F OVER DEEPER SNOW COVER FROM
I-74 NE TO THE MID UPPER 30S FROM SPRINGFIELD TO ROBINSON WHERE NO
SNOW COVER.
HUETTL
&&
.AVIATION...
ISSUED 1150 AM CST SAT JAN 17 2009
OVERCAST MVFR CEILINGS NW OF THE IL RIVER AT PIA WILL SPREAD SE
TO TO I-55 AT BMI AND SPI FROM 19Z-20Z AND DEC AND CMI FROM 20Z-21Z.
OVERCAST MVFR CEILINGS WILL LIKELY CONTINUE THROUGH SUNDAY MORNING.
THIS DUE TO LOW PRESSURE OVER WESTERN LOWER MI THAT MOVES ACROSS
THE GREAT LAKES WITH UPPER LEVEL TROF DIGGING OVER THE OHIO VALLEY.
CONTINUED CHANCE OF FLURRIES FROM MID AFTERNOON INTO TONIGHT AND
COULD LINGER INTO SUNDAY. BRUNT OF LIGHT SNOW AND VISIBILITY
RESTRICTIONS WILL BE NE OF I-74 THROUGH SUNDAY MORNING. STRONG SSW
WINDS 15 TO 20 KTS WITH GUSTS OF 25 TO 30 KTS WILL TURN WEST
BEHIND A COLD FRONT THAT IS ALONG THE IA/IL BORDER AND RACES SE
ACROSS CENTRAL IL DURING THIS AFTERNOON AND DIMINISHG TO 10 TO 15
KTS TONIGHT AS THE WINDS TURN NW BY 06Z/MIDNIGHT TONIGHT.
HUETTL
&&
.PREV DISCUSSION...
ISSUED 259 AM CST SAT JAN 17 2009
HIGH PRESSURE RIDGE SLIDING OFF TO THE ATLANTIC COAST THIS
MORNING...WITH SOUTHERLY FLOW STARTING OVER THE REGION...BRINGING
VERY WELCOME WARMER AIR INTO THE REGION...ALBEIT ONLY SLIGHTLY
WARMER. ANOTHER LOW MOVING INTO THE NRN PLAINS...AND TROFFING IN
GENERAL OVER THE ERRN HALF OF THE CONUS AT 500MB. NEXT COUPLE OF
ISSUES FOR THE FORECAST ARE SHORTWAVES. TIMING IS A BIT ALL OVER
THE PLACE WITH THE MODELS. OTHER ISSUES ARE TEMPERATURES
MODERATING A BIT...AND WINDS PICKING UP TODAY AS THE SFC LOW FROM
THE PLAINS MAKES ITS WAY TO THE MIDWEST.
SHORT TERM...TODAY AND TOMORROW...
LOW PRESSURE MAKING ITS WAY OUT OF THE PLAINS WILL TRACK ACROSS
THE GREAT LAKES. AHEAD OF THE LOW...STRONG SOUTHERLY FLOW WILL
SET UP...GUSTING INTO THE AFTERNOON WITH A TIGHTENING PRESSURE
GRADIENT AND SOME LIMITED MOMENTUM TRANSFER FROM JUST OFF THE SFC.
TEMPERATURES WILL MODERATE CONSIDERABLY FROM WHERE THEY HAVE
BEEN...WITH MUCH OF CENTRAL ILLINOIS GETTING INTO THE UPPER 20S
AND LOWER 30S. AREAS SOUTH OF INTERSTATE 72 WILL LIKELY SEE MID TO
UPPER 30S IN THE ABSENCE OF A SIGNIFICANT SNOWPACK.
WITH CYCLONIC FLOW ALOFT AND PLENTY OF MOISTURE...CLOUDS WILL
REMAIN OVER CENTRAL ILLINOIS THROUGH MUCH OF THE WEEKEND...THOUGH
THE RH GRADIENT ALOFT IS JUST TO THE SW IN ILLINOIS. OVERNIGHT
TONIGHT WILL SEE A BIT OF FLURRY ACTIVITY OUT OF THOSE
CLOUDS...THOUGH MORE SNOW WILL BE EXPECTED SUNDAY AFTERNOON AND
EVENING. A SHORTWAVE IS DIVING INTO THE REGION JUST A LITTLE BIT
EARLIER IN THE 00Z MODEL RUNS. HAVE PUT A 24 POP PLACE HOLDER IN
THE MOST LIKELY TIME FRAME...SUNDAY AFTER 18Z...AND FADING TO THE
SE BEFORE MONDAY AT 06Z. STILL...THE SNOWFALL AMOUNTS WILL REMAIN
BELOW AN INCH...JUST WANTED TO PUNCH IT UP A BIT MORE THAN
FLURRIES.
LONG TERM...MONDAY THROUGH WEDNESDAY...
A BIT OF A BREAK FROM THE WILDER FLUCTUATIONS AS THE UPPER LEVEL
TROF FINALLY PULLS OFF TO THE EAST...LEAVING SLIGHTLY WESTERLY
WINDS AT THE SURFACE. AFTER A SLIGHTLY COLDER MONDAY...TEMPS WILL
BE TRYING TO GET OVER THE FREEZING MARK FOR THE FIRST HALF OF NEXT WEEK.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
| 
