[top]
000
FXUS63 KMPX 200439
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1139 PM CDT FRI SEP 19 2008
.AVIATION.../06Z TAF ISSUANCE/
AVIATION CONCERNS ARE MINIMAL OVER THE UPCOMING 24 HOURS. ANY
CHANCE FOR A SHRA OVERNIGHT SHOULD BE SOUTH OF THE AIRPORTS...
WITH ONLY A FEW MID HIGH CLOUDS EXPECTED OVER THE AREA. KSTC IS
SEEING SOME LIGHT FOG NOW... AND COULD CONTINUE TO SEE SOME MVFR
VISIBILITIES OVER THE REMAINDER OF THE NIGHT OWING TO LIGHT WINDS
AND SOME LIGHT RAIN WHICH FELL IN THAT VICINITY EARLIER TODAY.
KEAU COULD ALSO SEE A BIT OF FOG LATER TONIGHT... BUT DO NOT
ANTICIPATE ANYTHING TOO WIDESPREAD WITH DRIER AIR AND LOWER
DEWPOINTS FILTERING IN FROM THE NORTH. THERE WILL BE A BIT OF
SHEAR IN THE BOTTOM FEW THOUSAND FEET... WITH A 25KT OR SO WIND
MAXIMA AROUND 2K FEET THROUGH 10Z OR SO... BUT THINGS DO NOT
APPEAR FOCUSED SUFFICIENTLY TO INCLUDED WIND SHEAR IN THE TAFS.
OTHERWISE... LOOK FOR LIGHT WINDS AND VFR CONDITIONS SATURDAY AND
SATURDAY NIGHT.
&&
.PREV DISCUSSION...
/ISSUED 833 PM CDT FRI SEP 19 2008/
UPDATE TO FORECAST WILL MAINLY BE TO UPDATE WORDING FOR THE
OVERNIGHT PERIOD... WITH MINIMAL CHANGES TO THE GOING FORECAST.
FRONTAL BOUNDARY CONTINUES TO SLOWLY SAG SOUTHEASTWARD... WITH
CONVECTION DISSIPATING AS DAYTIME INSTABILITY FADES. SOME ELEVATED
INSTABILITY WILL REMAIN ACROSS THE SOUTHERN PORTION OF THE AREA
THROUGH THE OVERNIGHT HOURS... ALTHOUGH THERE APPEARS TO BE VERY
LIMITED FORCING TO GET ANY ELEVATED ACTIVITY GOING. HOWEVER...
WITH THE NAM... RUC... AND LOCAL LAPSWRF KEEPING SOME NEARLY
SATURATED RH IN THE 850-700MB LAYER THROUGH 12Z IT WOULD BE TOUGH
TO RULE OUT AN ISOLATED SHRA/TSRA. THE BETTER FORCING... OWING TO
FRONTOGENESIS AND THE ACTUAL 1000-850MB BAROCLINIC ZONE... IS
FARTHER NORTH NEAR WHERE THE STRONGER CONVECTION IN NORTHEAST
MINNESOTA WAS EARLIER IN THE EVENING. THIS DOES DROP
SOUTHEASTWARD OVERNIGHT... ALTHOUGH IT WEAKENS AND WITH THE
BOUNDARY LAYER STABILIZING... DO NOT BELIEVE IT WILL BE ABLE TO
KICK OFF ANY FURTHER ACTIVITY. KMPX 00Z RAOB SUGGESTED BEST
POTENTIAL FOR ANY ELEVATED PARCEL WILL BE FROM AROUND 800MB...
WITH THE POTENTIAL OF 400-800 J/KG CAPE... SO IF SOMETHING CAN BE
KICKED OFF THERE IS STILL A CHANCE FOR SOME THUNDER. SO... WILL
MAINTAIN THE VERY LOW SLIGHT CHANCE POPS IN THE PREVIOUS FORECAST
FOR THE SOUTHEAST PORTION OF THE AREA FOR THE OVERNIGHT HOURS.
UPDATES TO CLOUD COVER AND TEMPERATURES WILL BE MINOR... AND WILL
SIMPLY REFLECT CURRENT TRENDS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
TRH
[top]
000
FXUS63 KDLH 200437
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1137 PM CDT FRI SEP 19 2008
.UPDATE...THINGS HAVE REALLY CALMED DOWN AS OF MID/LATE EVENING.
STILL THINK THERE COULD BE A FEW SPRINKLES OVERNIGHT...AND HAVE
ADDED THIS TO THE ZONES/GRIDS. HAVE ALSO ADDED PATCHY FOG MENTION
WITH A FEW PLACES SEEING SOME VSBY RESTRICTIONS AS OF 11 PM.
&&
.PREV DISCUSSION... /ISSUED 819 PM CDT FRI SEP 19 2008/
UPDATE...THE STORMS HAVE FINALLY STARTED TO SHOW SOME SIGN OF
BREAKING UP AND HAVE WEAKENED SOMEWHAT AS OF 815 PM. THIS IS ABOUT
ON TRACK WITH THE CURRENT THINKING OF STORMS DIMINISHING BETWEEN
01Z AND 0130Z...AND DISSIPATING BETWEEN 02Z AND 03Z. THE STORMS
SEEM TO HAVE BEEN KICKED OFF IN AN AREA OF DRY MID/UPPER LEVEL AIR
PER WATER VAPOR...WITH FAVORABLE LOW LEVEL INSTABILITY AND
THERMODYNAMIC PROFILE/LAPSE RATES. ALSO HELPED ALONG BY FAVORABLE
EFFECTIVE SHEAR AND THE FRONTAL BOUNDARY. WITH SUNSET...THE STORMS
SHOULD DIMINISH NICELY DURING THE REMAINDER OF THE
EVENING...ALTHOUGH WILL STILL CARRY ISOLATED MENTION THROUGH
MIDNIGHT. OTHER THAN THAT...ZONES/GRIDS APPEAR TO BE IN GOOD SHAPE
AND WILL LIKELY NOT MAKE MANY CHANGES TO THEM FOR THE OVERNIGHT.
EXPECT TO SEND ZFP AND UPDATED GRIDS BETWEEN 830 AND 9 PM. WE
WOULD GREATLY APPRECIATE CALLING ANY REPORTS INTO THE NWS THIS
EVENING.
PREV DISCUSSION... /ISSUED 734 PM CDT FRI SEP 19 2008/
MESOSCALE UPDATE...THE SEVERE STORM ACROSS NORTHERN LAKE COUNTY
HAD MAINTAINED ITSELF NICELY OVER THE PAST FEW HOURS. WITHIN THE
PAST 15 MINUTES OR SO...IT STARTED TO EXHIBIT SOME SIGNS OF
DEVELOPING A HOOK ECHO...AND WE HAVE ISSUED A TORNADO WARNING.
OVER THE PAST FEW MINUTES...THE STORM HAD STARTED TO UNDERGO A
TRANSFORMATION YET AGAIN. THE STORM WAS MOVING THROUGH A SPARSELY
POPULATED AREA...AND WE HAVE NOT HAD ANY REPORTS AS OF YET. STILL
LOOKING LIKE A CHANCE OF SEVERE THROUGH 01Z...OR PERHAPS 0130Z...AND
THEN DIMINISHING. MESOANALYSIS INDICATES SOME TORNADO
POTENTIAL...ALTHOUGH THINK LCL LEVELS MAY BE A BIT HIGH. IF ANYONE
HAS REPORTS IN THIS AREA...PLEASE RELAY THEM TO US AT THE NWS.
PREV DISCUSSION... /ISSUED 648 PM CDT FRI SEP 19 2008/
MESOSCALE UPDATE...THE STORM NEAR BASSWOOD LAKE HAD STRENGTHENED
CONSIDERABLY AS OF 640 PM...WITH MAX DBZ OF AROUND 70 DBZ.
DEFINITELY NOT BAD FOR MID/LATE SEPTEMBER. FOR THE DAY...50 DBZ
AROUND 25-28K SHOULD BE SEVERE...BUT THIS PARTICULAR STORM HAD A
50 DBZ HEIGHT OF AROUND 35K FEET. THE RUC PICKED UP ON THIS STORM
ABSOLUTELY PHENOMENALLY...ALBEIT A BIT FURTHER WEST. THE RUC KEEPS
THIS STUFF AROUND THROUGH AROUND 01Z...AND THEN TRIES TO DISSIPATE
THE STORMS FROM 02-03Z. THIS THINKING SOUNDS GOOD WITH SUNSET
APPROACHING. ADDITIONAL STORMS MAY YET DEVELOP TO THE SOUTH AND
WEST OF THIS AREA...ALONG THE FRONTAL BOUNDARY...SO WILL KEEP A
CLOSE EYE FOR NEW STORM DEVELOPMENT GIVEN SOME TCU DEVELOPMENT.
PREV DISCUSSION... /ISSUED 620 PM CDT FRI SEP 19 2008/
UPDATE...HAVE UPDATED ZONES/GRIDS TO ADD ISOLATED STORMS ACROSS
THE ENTIRE REGION WITH FRONT MOVING SOUTHEAST ACROSS THE AREA. ONE
SUCH STORM DEVELOPED NORTHWEST OF BASSWOOD LAKE...AND WAS MOVING
E/SE. WILL MONITOR THIS STORM IN THE EVENT IT STRENGTHENS FURTHER
WHEN IT ENTERS INTO NRN LAKE/NW COOK COUNTIES. RIGHT NOW MOST OF
THE ENERGY WAS NORTH OF THE BORDER...BUT WILL SOON MOVE INTO THE
CWA. STRONG WIND CONVERGENCE ALONG THE FRONT COULD IGNITE A FEW
MORE STORMS ALONG THE FRONT THIS EVENING. MESOANALYSIS PAGE OF SPC
INDICATES MUCAPE OF AROUND 2000 J/KG WITH LITTLE INHIBITION. STEEP
LAPSE RATES AND MOISTURE POOLING ALONG THE FRONT COULD LEAD TO
FURTHER DEVELOPMENT IF THE STORMS ARE ABLE TO SUSTAIN THEMSELVES.
FIRST THOUGHTS ARE THAT THE POTENTIAL WILL EXIST FOR A FEW STORMS
TO BECOME SEVERE OVER THE NEXT FEW HOURS...BUT WILL DIMINISH
RAPIDLY AS SUNSET APPROACHES. SUPERCELL COMPOSITE PARAMETER OF
BETWEEN 4 AND 8 OFF THE SPC WEBSITE...SO WILL BE TAKING THE THREAT
VERY SERIOUSLY THIS EVENING.
PREV DISCUSSION... /ISSUED 356 PM CDT FRI SEP 19 2008/
DISCUSSION...LATEST KDLH RADAR IMAGERY SHOWS A LINE OF SCATTERED
SHOWERS AND THUNDERSTORMS EXTENDING ACROSS NORTHWESTERN WISCONSIN
AND PINE COUNTY THIS AFTERNOON. THIS ACTIVITY IS ASSOCIATED WITH
AN UPPER LEVEL SHORTWAVE DIGGING SE ACROSS THE AREA...PRECEDING
THE COLD FRONT WHICH IS JUST ENTERING THE NW CORNER OF OUR CWA.
THE PRECIPITATION WILL CONTINUE TO DISSIPATE THROUGH EARLY THIS
EVENING...AND END BY MIDNIGHT. THE COLD FRONT WILL TRACK SOUTHEAST
ACROSS OUR FCST AREA TONIGHT...EXITING TO THE SOUTH OF THE
NORTHLAND LATE TONIGHT. HIGH PRESSURE FROM CANADA WILL THEN BUILD
SOUTH OVER THE CWA TOMORROW...BRINGING COOLER TEMPERATURES AND DRY
CONDITIONS.
THE CENTER OF THE HIGH WILL MOVE OFF TO THE EAST OF OUR CWA ON
SUNDAY...ALLOWING FOR RETURN SOUTHERLY FLOW TO DEVELOP WHICH WILL
IN TURN INITIATE WAA ACROSS THE UPPER MIDWEST. AS MOISTURE AND
TEMPS INCREASE ACROSS THE AREA...THE AIRMASS WILL DESTABILIZE
SUNDAY THRU TUESDAY. A COLD FRONT IS PROGGED TO PROPAGATE ACROSS
OUR CWA TUESDAY AND TUESDAY NIGHT...TAPPING THIS INCREASING
MOISTURE AND INSTABILITY...AND BRINGING ANOTHER ROUND OF SHOWERS
AND STORMS TO OUR FCST AREA.
HIGH TEMPERATURES WILL DROP 10 TO 20 DEGREES ACROSS THE NORTHLAND
BETWEEN TODAY TO TOMORROW. AS WINDS TURN OUT OF THE
NORTHEAST...THE COOLER TEMPS WILL ESPECIALLY BE NOTICEABLE ALONG
THE LAKE SUPERIOR SHORELINE.
AVIATION...ISOLD -SHRA/-TSRA WILL AFFECT MAINLY KDLH AND KHYR
THROUGH 21-23Z TIME FRAME AS AN UPPER LEVEL SHORT WAVE CROSSES THE
WESTERN GREAT LAKES. A COLD FRONT IS FORECAST TO MOVE THROUGH NE MN
THIS EVENING AND NW WI OVERNIGHT. LOOK FOR A WIND SHIFT TO THE NW
AFTER FROPA. BY 12Z SATURDAY...THE WIND WILL SWING AROUND TO THE NE
AS HIGH PRESSURE FROM CANADA BUILDS INTO THE AREA.
&&
POINT TEMPS/POPS...
DLH 50 58 44 62 / 20 10 10 20
INL 38 58 39 68 / 10 10 10 20
BRD 50 68 48 73 / 10 10 10 10
HYR 50 66 41 69 / 20 10 10 20
ASX 51 59 43 65 / 20 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
DAP
000
FXUS63 KMPX 200133
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
833 PM CDT FRI SEP 19 2008
.DISCUSSION...
UPDATE TO FORECAST WILL MAINLY BE TO UPDATE WORDING FOR THE
OVERNIGHT PERIOD... WITH MINIMAL CHANGES TO THE GOING FORECAST.
FRONTAL BOUNDARY CONTINUES TO SLOWLY SAG SOUTHEASTWARD... WITH
CONVECTION DISSIPATING AS DAYTIME INSTABILITY FADES. SOME ELEVATED
INSTABILITY WILL REMAIN ACROSS THE SOUTHERN PORTION OF THE AREA
THROUGH THE OVERNIGHT HOURS... ALTHOUGH THERE APPEARS TO BE VERY
LIMITED FORCING TO GET ANY ELEVATED ACTIVITY GOING. HOWEVER...
WITH THE NAM... RUC... AND LOCAL LAPSWRF KEEPING SOME NEARLY
SATURATED RH IN THE 850-700MB LAYER THROUGH 12Z IT WOULD BE TOUGH
TO RULE OUT AN ISOLATED SHRA/TSRA. THE BETTER FORCING... OWING TO
FRONTOGENESIS AND THE ACTUAL 1000-850MB BAROCLINIC ZONE... IS
FARTHER NORTH NEAR WHERE THE STRONGER CONVECTION IN NORTHEAST
MINNESOTA WAS EARLIER IN THE EVENING. THIS DOES DROP
SOUTHEASTWARD OVERNIGHT... ALTHOUGH IT WEAKENS AND WITH THE
BOUNDARY LAYER STABILIZING... DO NOT BELIEVE IT WILL BE ABLE TO
KICK OFF ANY FURTHER ACTIVITY. KMPX 00Z RAOB SUGGESTED BEST
POTENTIAL FOR ANY ELEVATED PARCEL WILL BE FROM AROUND 800MB...
WITH THE POTENTIAL OF 400-800 J/KG CAPE... SO IF SOMETHING CAN BE
KICKED OFF THERE IS STILL A CHANCE FOR SOME THUNDER. SO... WILL
MAINTAIN THE VERY LOW SLIGHT CHANCE POPS IN THE PREVIOUS FORECAST
FOR THE SOUTHEAST PORTION OF THE AREA FOR THE OVERNIGHT HOURS.
UPDATES TO CLOUD COVER AND TEMPERATURES WILL BE MINOR... AND WILL
SIMPLY REFLECT CURRENT TRENDS.
&&
.AVIATION.../00Z TAF ISSUANCE/
/ISSUED 534 PM CDT FRI SEP 19 2008/
VFR CONDS WL PREVAIL THRU THE VALID TAF PD. LEFT A VCSH DURG THE
FIRST FEW HRS OF THE TAF AT MSP AND RNH WITH RESIDUAL AFTN SHRA
REMAINING NEAR THOSE SITES. WINDS WL SHIFT TO A NERLY DIRN BEHIND
THE CDFNTL PASSAGE LATE TNGT...WITH SPDS REMAINING BLO 10 KTS DURG
THE AFTN TMRW.
&&
.PREV DISCUSSION...
/ISSUED AT 144 PM CDT FRI SEP 19 2008/
WEAK FRONTAL BOUNDARY ALONG WITH SOME WEAK POSITIVE VORTICITY
ADVECTION WAS AIDING THE DEVELOPMENT OF SHRA/TSRA AHEAD OF THE FRONT
ACRS PORTIONS OF SOUTHERN MN INTO WESTERN WISCONSIN. THE LATEST IR
SATELLITE IMAGERY SHOWED A MINOR IMPLUSE OVR CNTRL MN...THIS WAVE
WAS ASLO HELPING WITH THE INITATION AND MAINTENANCE OF THE PRECIP.
THE IMPLUSE IS FORECAST TO MOVE EAST ACRS NORTHERN WI THIS EVENING.
WL KEEP SOME SMALL POPS GOING OVER THE SOUTHERN THIRD OF THE STATE
THIS EVENING.
ELSEWHERE...SKIES ARE EXPECTED TO CLEAR NORTH OF THE FRONTAL
BOUNDARY OVERNIGHT...WHILE SOME PATCHY CLOUDS OR BROKEN LAYER OCCURS
JUST SOUTH OF IT.
SATURDAY...WEAK FRONT STALLED OVER THE SOUTHERN THIRD OF THE
STATE...WILL BEGIN TO LIFT NORTH AS WARM FRONT LATE IN THE DAY. WL
GO ALONG WITH PREVIOUS FORECAST...A LEAVE SOME SMALL POPS IN
VICINITY OF THE FRONT.
MEDIUM RANGE IN GOOD AGREEMENT...WITH THE OVERALL UPPER AIR PATTERN
INTO THE NEXT WEEK. LONGWAVE UPPER RIDGE WILL SLOWLY BUILD AND MOVE
EAST OVER THE CENTRAL CONUS. MODERATE SUBSIDENCE ALOFT SHOULD KEEP
MOST AREAS DRY SATURDAY NIGHT INTO MONDAY MORNING.
BY MONDAY AFTERNOON...THE UPPER AIR PATTERN SHIFTS TO MORE
SOUTHWESTERLY AIRFLOW OVER THE MIDWEST WITH PRECIP CHANCES
INCREASING FROM WEST TO EAST OVER THE FORECAST AREA MONDAY INTO
TUESDAY. THE SHORT WAVE TROUGH FINALLY LIFTS EAST THROUGH OUR CWA
WEDNESDAY.
EXTENDED OUTLOOK...LTL CHANGE TO THE HPC GUIDANCE AND LEFT SOME POPS
TOWARD END OF NEW WORK WEEK. SHORTWAVE TROUGH FORECAST TO CARVE OUT
OVER THE UPPER MIDWEST...SATURDAY...LOOKS QUESTIONABLE...BY THE
LATEST GFS90 MODEL. FAST ZONAL FLOW OVER THE NORTHERN TIER U.S.
FORECAST CONFIDENCE IS SLOW.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
TRH/KAT/JVM
000
FXUS63 KDLH 200119
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
819 PM CDT FRI SEP 19 2008
.UPDATE...THE STORMS HAVE FINALLY STARTED TO SHOW SOME SIGN OF
BREAKING UP AND HAVE WEAKENED SOMEWHAT AS OF 815 PM. THIS IS ABOUT
ON TRACK WITH THE CURRENT THINKING OF STORMS DIMINISHING BETWEEN
01Z AND 0130Z...AND DISSIPATING BETWEEN 02Z AND 03Z. THE STORMS
SEEM TO HAVE BEEN KICKED OFF IN AN AREA OF DRY MID/UPPER LEVEL AIR
PER WATER VAPOR...WITH FAVORABLE LOW LEVEL INSTABILITY AND
THERMODYNAMIC PROFILE/LAPSE RATES. ALSO HELPED ALONG BY FAVORABLE
EFFECTIVE SHEAR AND THE FRONTAL BOUNDARY. WITH SUNSET...THE STORMS
SHOULD DIMINISH NICELY DURING THE REMAINDER OF THE
EVENING...ALTHOUGH WILL STILL CARRY ISOLATED MENTION THROUGH
MIDNIGHT. OTHER THAN THAT...ZONES/GRIDS APPEAR TO BE IN GOOD SHAPE
AND WILL LIKELY NOT MAKE MANY CHANGES TO THEM FOR THE OVERNIGHT.
EXPECT TO SEND ZFP AND UPDATED GRIDS BETWEEN 830 AND 9 PM. WE
WOULD GREATLY APPRECIATE CALLING ANY REPORTS INTO THE NWS THIS
EVENING.
&&
.PREV DISCUSSION... /ISSUED 734 PM CDT FRI SEP 19 2008/
MESOSCALE UPDATE...THE SEVERE STORM ACROSS NORTHERN LAKE COUNTY
HAD MAINTAINED ITSELF NICELY OVER THE PAST FEW HOURS. WITHIN THE
PAST 15 MINUTES OR SO...IT STARTED TO EXHIBIT SOME SIGNS OF
DEVELOPING A HOOK ECHO...AND WE HAVE ISSUED A TORNADO WARNING.
OVER THE PAST FEW MINUTES...THE STORM HAD STARTED TO UNDERGO A
TRANSFORMATION YET AGAIN. THE STORM WAS MOVING THROUGH A SPARSELY
POPULATED AREA...AND WE HAVE NOT HAD ANY REPORTS AS OF YET. STILL
LOOKING LIKE A CHANCE OF SEVERE THROUGH 01Z...OR PERHAPS 0130Z...AND
THEN DIMINISHING. MESOANALYSIS INDICATES SOME TORNADO
POTENTIAL...ALTHOUGH THINK LCL LEVELS MAY BE A BIT HIGH. IF ANYONE
HAS REPORTS IN THIS AREA...PLEASE RELAY THEM TO US AT THE NWS.
PREV DISCUSSION... /ISSUED 648 PM CDT FRI SEP 19 2008/
MESOSCALE UPDATE...THE STORM NEAR BASSWOOD LAKE HAD STRENGTHENED
CONSIDERABLY AS OF 640 PM...WITH MAX DBZ OF AROUND 70 DBZ.
DEFINITELY NOT BAD FOR MID/LATE SEPTEMBER. FOR THE DAY...50 DBZ
AROUND 25-28K SHOULD BE SEVERE...BUT THIS PARTICULAR STORM HAD A
50 DBZ HEIGHT OF AROUND 35K FEET. THE RUC PICKED UP ON THIS STORM
ABSOLUTELY PHENOMENALLY...ALBEIT A BIT FURTHER WEST. THE RUC KEEPS
THIS STUFF AROUND THROUGH AROUND 01Z...AND THEN TRIES TO DISSIPATE
THE STORMS FROM 02-03Z. THIS THINKING SOUNDS GOOD WITH SUNSET
APPROACHING. ADDITIONAL STORMS MAY YET DEVELOP TO THE SOUTH AND
WEST OF THIS AREA...ALONG THE FRONTAL BOUNDARY...SO WILL KEEP A
CLOSE EYE FOR NEW STORM DEVELOPMENT GIVEN SOME TCU DEVELOPMENT.
PREV DISCUSSION... /ISSUED 620 PM CDT FRI SEP 19 2008/
UPDATE...HAVE UPDATED ZONES/GRIDS TO ADD ISOLATED STORMS ACROSS
THE ENTIRE REGION WITH FRONT MOVING SOUTHEAST ACROSS THE AREA. ONE
SUCH STORM DEVELOPED NORTHWEST OF BASSWOOD LAKE...AND WAS MOVING
E/SE. WILL MONITOR THIS STORM IN THE EVENT IT STRENGTHENS FURTHER
WHEN IT ENTERS INTO NRN LAKE/NW COOK COUNTIES. RIGHT NOW MOST OF
THE ENERGY WAS NORTH OF THE BORDER...BUT WILL SOON MOVE INTO THE
CWA. STRONG WIND CONVERGENCE ALONG THE FRONT COULD IGNITE A FEW
MORE STORMS ALONG THE FRONT THIS EVENING. MESOANALYSIS PAGE OF SPC
INDICATES MUCAPE OF AROUND 2000 J/KG WITH LITTLE INHIBITION. STEEP
LAPSE RATES AND MOISTURE POOLING ALONG THE FRONT COULD LEAD TO
FURTHER DEVELOPMENT IF THE STORMS ARE ABLE TO SUSTAIN THEMSELVES.
FIRST THOUGHTS ARE THAT THE POTENTIAL WILL EXIST FOR A FEW STORMS
TO BECOME SEVERE OVER THE NEXT FEW HOURS...BUT WILL DIMINISH
RAPIDLY AS SUNSET APPROACHES. SUPERCELL COMPOSITE PARAMETER OF
BETWEEN 4 AND 8 OFF THE SPC WEBSITE...SO WILL BE TAKING THE THREAT
VERY SERIOUSLY THIS EVENING.
PREV DISCUSSION... /ISSUED 356 PM CDT FRI SEP 19 2008/
DISCUSSION...LATEST KDLH RADAR IMAGERY SHOWS A LINE OF SCATTERED
SHOWERS AND THUNDERSTORMS EXTENDING ACROSS NORTHWESTERN WISCONSIN
AND PINE COUNTY THIS AFTERNOON. THIS ACTIVITY IS ASSOCIATED WITH
AN UPPER LEVEL SHORTWAVE DIGGING SE ACROSS THE AREA...PRECEDING
THE COLD FRONT WHICH IS JUST ENTERING THE NW CORNER OF OUR CWA.
THE PRECIPITATION WILL CONTINUE TO DISSIPATE THROUGH EARLY THIS
EVENING...AND END BY MIDNIGHT. THE COLD FRONT WILL TRACK SOUTHEAST
ACROSS OUR FCST AREA TONIGHT...EXITING TO THE SOUTH OF THE
NORTHLAND LATE TONIGHT. HIGH PRESSURE FROM CANADA WILL THEN BUILD
SOUTH OVER THE CWA TOMORROW...BRINGING COOLER TEMPERATURES AND DRY
CONDITIONS.
THE CENTER OF THE HIGH WILL MOVE OFF TO THE EAST OF OUR CWA ON
SUNDAY...ALLOWING FOR RETURN SOUTHERLY FLOW TO DEVELOP WHICH WILL
IN TURN INITIATE WAA ACROSS THE UPPER MIDWEST. AS MOISTURE AND
TEMPS INCREASE ACROSS THE AREA...THE AIRMASS WILL DESTABILIZE
SUNDAY THRU TUESDAY. A COLD FRONT IS PROGGED TO PROPAGATE ACROSS
OUR CWA TUESDAY AND TUESDAY NIGHT...TAPPING THIS INCREASING
MOISTURE AND INSTABILITY...AND BRINGING ANOTHER ROUND OF SHOWERS
AND STORMS TO OUR FCST AREA.
HIGH TEMPERATURES WILL DROP 10 TO 20 DEGREES ACROSS THE NORTHLAND
BETWEEN TODAY TO TOMORROW. AS WINDS TURN OUT OF THE
NORTHEAST...THE COOLER TEMPS WILL ESPECIALLY BE NOTICEABLE ALONG
THE LAKE SUPERIOR SHORELINE.
AVIATION...ISOLD -SHRA/-TSRA WILL AFFECT MAINLY KDLH AND KHYR
THROUGH 21-23Z TIME FRAME AS AN UPPER LEVEL SHORT WAVE CROSSES THE
WESTERN GREAT LAKES. A COLD FRONT IS FORECAST TO MOVE THROUGH NE MN
THIS EVENING AND NW WI OVERNIGHT. LOOK FOR A WIND SHIFT TO THE NW
AFTER FROPA. BY 12Z SATURDAY...THE WIND WILL SWING AROUND TO THE NE
AS HIGH PRESSURE FROM CANADA BUILDS INTO THE AREA.
&&
POINT TEMPS/POPS...
DLH 50 58 44 62 / 20 10 10 20
INL 42 58 39 68 / 20 10 10 20
BRD 50 68 48 73 / 20 10 10 10
HYR 50 66 41 69 / 20 10 10 20
ASX 51 59 43 65 / 20 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
DAP
000
FXUS63 KDLH 200034
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
734 PM CDT FRI SEP 19 2008
.MESOSCALE UPDATE...THE SEVERE STORM ACROSS NORTHERN LAKE COUNTY
HAD MAINTAINED ITSELF NICELY OVER THE PAST FEW HOURS. WITHIN THE
PAST 15 MINUTES OR SO...IT STARTED TO EXHIBIT SOME SIGNS OF
DEVELOPING A HOOK ECHO...AND WE HAVE ISSUED A TORNADO WARNING.
OVER THE PAST FEW MINUTES...THE STORM HAD STARTED TO UNDERGO A
TRANSFORMATION YET AGAIN. THE STORM WAS MOVING THROUGH A SPARSELY
POPULATED AREA...AND WE HAVE NOT HAD ANY REPORTS AS OF YET. STILL
LOOKING LIKE A CHANCE OF SEVERE THROUGH 01Z...OR PERHAPS 0130Z...AND
THEN DIMINISHING. MESOANALYSIS INDICATES SOME TORNADO
POTENTIAL...ALTHOUGH THINK LCL LEVELS MAY BE A BIT HIGH. IF ANYONE
HAS REPORTS IN THIS AREA...PLEASE RELAY THEM TO US AT THE NWS.
&&
.PREV DISCUSSION... /ISSUED 648 PM CDT FRI SEP 19 2008/
MESOSCALE UPDATE...THE STORM NEAR BASSWOOD LAKE HAD STRENGTHENED
CONSIDERABLY AS OF 640 PM...WITH MAX DBZ OF AROUND 70 DBZ.
DEFINITELY NOT BAD FOR MID/LATE SEPTEMBER. FOR THE DAY...50 DBZ
AROUND 25-28K SHOULD BE SEVERE...BUT THIS PARTICULAR STORM HAD A
50 DBZ HEIGHT OF AROUND 35K FEET. THE RUC PICKED UP ON THIS STORM
ABSOLUTELY PHENOMENALLY...ALBEIT A BIT FURTHER WEST. THE RUC KEEPS
THIS STUFF AROUND THROUGH AROUND 01Z...AND THEN TRIES TO DISSIPATE
THE STORMS FROM 02-03Z. THIS THINKING SOUNDS GOOD WITH SUNSET
APPROACHING. ADDITIONAL STORMS MAY YET DEVELOP TO THE SOUTH AND
WEST OF THIS AREA...ALONG THE FRONTAL BOUNDARY...SO WILL KEEP A
CLOSE EYE FOR NEW STORM DEVELOPMENT GIVEN SOME TCU DEVELOPMENT.
PREV DISCUSSION... /ISSUED 620 PM CDT FRI SEP 19 2008/
UPDATE...HAVE UPDATED ZONES/GRIDS TO ADD ISOLATED STORMS ACROSS
THE ENTIRE REGION WITH FRONT MOVING SOUTHEAST ACROSS THE AREA. ONE
SUCH STORM DEVELOPED NORTHWEST OF BASSWOOD LAKE...AND WAS MOVING
E/SE. WILL MONITOR THIS STORM IN THE EVENT IT STRENGTHENS FURTHER
WHEN IT ENTERS INTO NRN LAKE/NW COOK COUNTIES. RIGHT NOW MOST OF
THE ENERGY WAS NORTH OF THE BORDER...BUT WILL SOON MOVE INTO THE
CWA. STRONG WIND CONVERGENCE ALONG THE FRONT COULD IGNITE A FEW
MORE STORMS ALONG THE FRONT THIS EVENING. MESOANALYSIS PAGE OF SPC
INDICATES MUCAPE OF AROUND 2000 J/KG WITH LITTLE INHIBITION. STEEP
LAPSE RATES AND MOISTURE POOLING ALONG THE FRONT COULD LEAD TO
FURTHER DEVELOPMENT IF THE STORMS ARE ABLE TO SUSTAIN THEMSELVES.
FIRST THOUGHTS ARE THAT THE POTENTIAL WILL EXIST FOR A FEW STORMS
TO BECOME SEVERE OVER THE NEXT FEW HOURS...BUT WILL DIMINISH
RAPIDLY AS SUNSET APPROACHES. SUPERCELL COMPOSITE PARAMETER OF
BETWEEN 4 AND 8 OFF THE SPC WEBSITE...SO WILL BE TAKING THE THREAT
VERY SERIOUSLY THIS EVENING.
PREV DISCUSSION... /ISSUED 356 PM CDT FRI SEP 19 2008/
DISCUSSION...LATEST KDLH RADAR IMAGERY SHOWS A LINE OF SCATTERED
SHOWERS AND THUNDERSTORMS EXTENDING ACROSS NORTHWESTERN WISCONSIN
AND PINE COUNTY THIS AFTERNOON. THIS ACTIVITY IS ASSOCIATED WITH
AN UPPER LEVEL SHORTWAVE DIGGING SE ACROSS THE AREA...PRECEDING
THE COLD FRONT WHICH IS JUST ENTERING THE NW CORNER OF OUR CWA.
THE PRECIPITATION WILL CONTINUE TO DISSIPATE THROUGH EARLY THIS
EVENING...AND END BY MIDNIGHT. THE COLD FRONT WILL TRACK SOUTHEAST
ACROSS OUR FCST AREA TONIGHT...EXITING TO THE SOUTH OF THE
NORTHLAND LATE TONIGHT. HIGH PRESSURE FROM CANADA WILL THEN BUILD
SOUTH OVER THE CWA TOMORROW...BRINGING COOLER TEMPERATURES AND DRY
CONDITIONS.
THE CENTER OF THE HIGH WILL MOVE OFF TO THE EAST OF OUR CWA ON
SUNDAY...ALLOWING FOR RETURN SOUTHERLY FLOW TO DEVELOP WHICH WILL
IN TURN INITIATE WAA ACROSS THE UPPER MIDWEST. AS MOISTURE AND
TEMPS INCREASE ACROSS THE AREA...THE AIRMASS WILL DESTABILIZE
SUNDAY THRU TUESDAY. A COLD FRONT IS PROGGED TO PROPAGATE ACROSS
OUR CWA TUESDAY AND TUESDAY NIGHT...TAPPING THIS INCREASING
MOISTURE AND INSTABILITY...AND BRINGING ANOTHER ROUND OF SHOWERS
AND STORMS TO OUR FCST AREA.
HIGH TEMPERATURES WILL DROP 10 TO 20 DEGREES ACROSS THE NORTHLAND
BETWEEN TODAY TO TOMORROW. AS WINDS TURN OUT OF THE
NORTHEAST...THE COOLER TEMPS WILL ESPECIALLY BE NOTICEABLE ALONG
THE LAKE SUPERIOR SHORELINE.
AVIATION...ISOLD -SHRA/-TSRA WILL AFFECT MAINLY KDLH AND KHYR
THROUGH 21-23Z TIME FRAME AS AN UPPER LEVEL SHORT WAVE CROSSES THE
WESTERN GREAT LAKES. A COLD FRONT IS FORECAST TO MOVE THROUGH NE MN
THIS EVENING AND NW WI OVERNIGHT. LOOK FOR A WIND SHIFT TO THE NW
AFTER FROPA. BY 12Z SATURDAY...THE WIND WILL SWING AROUND TO THE NE
AS HIGH PRESSURE FROM CANADA BUILDS INTO THE AREA.
&&
POINT TEMPS/POPS...
DLH 50 58 44 62 / 20 10 10 20
INL 42 58 39 68 / 20 10 10 20
BRD 50 68 48 73 / 20 10 10 10
HYR 50 66 41 69 / 20 10 10 20
ASX 51 59 43 65 / 20 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
DAP
000
FXUS63 KDLH 192348
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
648 PM CDT FRI SEP 19 2008
.MESOSCALE UPDATE...THE STORM NEAR BASSWOOD LAKE HAD STRENGTHENED
CONSIDERABLY AS OF 640 PM...WITH MAX DBZ OF AROUND 70 DBZ.
DEFINITELY NOT BAD FOR MID/LATE SEPTEMBER. FOR THE DAY...50 DBZ
AROUND 25-28K SHOULD BE SEVERE...BUT THIS PARTICULAR STORM HAD A
50 DBZ HEIGHT OF AROUND 35K FEET. THE RUC PICKED UP ON THIS STORM
ABSOLUTELY PHENOMENALLY...ALBEIT A BIT FURTHER WEST. THE RUC KEEPS
THIS STUFF AROUND THROUGH AROUND 01Z...AND THEN TRIES TO DISSIPATE
THE STORMS FROM 02-03Z. THIS THINKING SOUNDS GOOD WITH SUNSET
APPROACHING. ADDITIONAL STORMS MAY YET DEVELOP TO THE SOUTH AND
WEST OF THIS AREA...ALONG THE FRONTAL BOUNDARY...SO WILL KEEP A
CLOSE EYE FOR NEW STORM DEVELOPMENT GIVEN SOME TCU DEVELOPMENT.
&&
.PREV DISCUSSION... /ISSUED 620 PM CDT FRI SEP 19 2008/
UPDATE...HAVE UPDATED ZONES/GRIDS TO ADD ISOLATED STORMS ACROSS
THE ENTIRE REGION WITH FRONT MOVING SOUTHEAST ACROSS THE AREA. ONE
SUCH STORM DEVELOPED NORTHWEST OF BASSWOOD LAKE...AND WAS MOVING
E/SE. WILL MONITOR THIS STORM IN THE EVENT IT STRENGTHENS FURTHER
WHEN IT ENTERS INTO NRN LAKE/NW COOK COUNTIES. RIGHT NOW MOST OF
THE ENERGY WAS NORTH OF THE BORDER...BUT WILL SOON MOVE INTO THE
CWA. STRONG WIND CONVERGENCE ALONG THE FRONT COULD IGNITE A FEW
MORE STORMS ALONG THE FRONT THIS EVENING. MESOANALYSIS PAGE OF SPC
INDICATES MUCAPE OF AROUND 2000 J/KG WITH LITTLE INHIBITION. STEEP
LAPSE RATES AND MOISTURE POOLING ALONG THE FRONT COULD LEAD TO
FURTHER DEVELOPMENT IF THE STORMS ARE ABLE TO SUSTAIN THEMSELVES.
FIRST THOUGHTS ARE THAT THE POTENTIAL WILL EXIST FOR A FEW STORMS
TO BECOME SEVERE OVER THE NEXT FEW HOURS...BUT WILL DIMINISH
RAPIDLY AS SUNSET APPROACHES. SUPERCELL COMPOSITE PARAMETER OF
BETWEEN 4 AND 8 OFF THE SPC WEBSITE...SO WILL BE TAKING THE THREAT
VERY SERIOUSLY THIS EVENING.
PREV DISCUSSION... /ISSUED 356 PM CDT FRI SEP 19 2008/
DISCUSSION...LATEST KDLH RADAR IMAGERY SHOWS A LINE OF SCATTERED
SHOWERS AND THUNDERSTORMS EXTENDING ACROSS NORTHWESTERN WISCONSIN
AND PINE COUNTY THIS AFTERNOON. THIS ACTIVITY IS ASSOCIATED WITH
AN UPPER LEVEL SHORTWAVE DIGGING SE ACROSS THE AREA...PRECEDING
THE COLD FRONT WHICH IS JUST ENTERING THE NW CORNER OF OUR CWA.
THE PRECIPITATION WILL CONTINUE TO DISSIPATE THROUGH EARLY THIS
EVENING...AND END BY MIDNIGHT. THE COLD FRONT WILL TRACK SOUTHEAST
ACROSS OUR FCST AREA TONIGHT...EXITING TO THE SOUTH OF THE
NORTHLAND LATE TONIGHT. HIGH PRESSURE FROM CANADA WILL THEN BUILD
SOUTH OVER THE CWA TOMORROW...BRINGING COOLER TEMPERATURES AND DRY
CONDITIONS.
THE CENTER OF THE HIGH WILL MOVE OFF TO THE EAST OF OUR CWA ON
SUNDAY...ALLOWING FOR RETURN SOUTHERLY FLOW TO DEVELOP WHICH WILL
IN TURN INITIATE WAA ACROSS THE UPPER MIDWEST. AS MOISTURE AND
TEMPS INCREASE ACROSS THE AREA...THE AIRMASS WILL DESTABILIZE
SUNDAY THRU TUESDAY. A COLD FRONT IS PROGGED TO PROPAGATE ACROSS
OUR CWA TUESDAY AND TUESDAY NIGHT...TAPPING THIS INCREASING
MOISTURE AND INSTABILITY...AND BRINGING ANOTHER ROUND OF SHOWERS
AND STORMS TO OUR FCST AREA.
HIGH TEMPERATURES WILL DROP 10 TO 20 DEGREES ACROSS THE NORTHLAND
BETWEEN TODAY TO TOMORROW. AS WINDS TURN OUT OF THE
NORTHEAST...THE COOLER TEMPS WILL ESPECIALLY BE NOTICEABLE ALONG
THE LAKE SUPERIOR SHORELINE.
AVIATION...ISOLD -SHRA/-TSRA WILL AFFECT MAINLY KDLH AND KHYR
THROUGH 21-23Z TIME FRAME AS AN UPPER LEVEL SHORT WAVE CROSSES THE
WESTERN GREAT LAKES. A COLD FRONT IS FORECAST TO MOVE THROUGH NE MN
THIS EVENING AND NW WI OVERNIGHT. LOOK FOR A WIND SHIFT TO THE NW
AFTER FROPA. BY 12Z SATURDAY...THE WIND WILL SWING AROUND TO THE NE
AS HIGH PRESSURE FROM CANADA BUILDS INTO THE AREA.
&&
POINT TEMPS/POPS...
DLH 78 50 58 44 / 30 20 10 10
INL 80 42 58 39 / 20 20 10 10
BRD 82 50 68 48 / 40 20 10 10
HYR 79 50 66 41 / 30 20 10 10
ASX 80 51 59 43 / 30 20 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
DAP
000
FXUS63 KDLH 192320
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
620 PM CDT FRI SEP 19 2008
.UPDATE...HAVE UPDATED ZONES/GRIDS TO ADD ISOLATED STORMS ACROSS
THE ENTIRE REGION WITH FRONT MOVING SOUTHEAST ACROSS THE AREA. ONE
SUCH STORM DEVELOPED NORTHWEST OF BASSWOOD LAKE...AND WAS MOVING
E/SE. WILL MONITOR THIS STORM IN THE EVENT IT STRENGTHENS FURTHER
WHEN IT ENTERS INTO NRN LAKE/NW COOK COUNTIES. RIGHT NOW MOST OF
THE ENERGY WAS NORTH OF THE BORDER...BUT WILL SOON MOVE INTO THE
CWA. STRONG WIND CONVERGENCE ALONG THE FRONT COULD IGNITE A FEW
MORE STORMS ALONG THE FRONT THIS EVENING. MESOANALYSIS PAGE OF SPC
INDICATES MUCAPE OF AROUND 2000 J/KG WITH LITTLE INHIBITION. STEEP
LAPSE RATES AND MOISTURE POOLING ALONG THE FRONT COULD LEAD TO
FURTHER DEVELOPMENT IF THE STORMS ARE ABLE TO SUSTAIN THEMSELVES.
FIRST THOUGHTS ARE THAT THE POTENTIAL WILL EXIST FOR A FEW STORMS
TO BECOME SEVERE OVER THE NEXT FEW HOURS...BUT WILL DIMINISH
RAPIDLY AS SUNSET APPROACHES. SUPERCELL COMPOSITE PARAMETER OF
BETWEEN 4 AND 8 OFF THE SPC WEBSITE...SO WILL BE TAKING THE THREAT
VERY SERIOUSLY THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 356 PM CDT FRI SEP 19 2008/
DISCUSSION...LATEST KDLH RADAR IMAGERY SHOWS A LINE OF SCATTERED
SHOWERS AND THUNDERSTORMS EXTENDING ACROSS NORTHWESTERN WISCONSIN
AND PINE COUNTY THIS AFTERNOON. THIS ACTIVITY IS ASSOCIATED WITH
AN UPPER LEVEL SHORTWAVE DIGGING SE ACROSS THE AREA...PRECEDING
THE COLD FRONT WHICH IS JUST ENTERING THE NW CORNER OF OUR CWA.
THE PRECIPITATION WILL CONTINUE TO DISSIPATE THROUGH EARLY THIS
EVENING...AND END BY MIDNIGHT. THE COLD FRONT WILL TRACK SOUTHEAST
ACROSS OUR FCST AREA TONIGHT...EXITING TO THE SOUTH OF THE
NORTHLAND LATE TONIGHT. HIGH PRESSURE FROM CANADA WILL THEN BUILD
SOUTH OVER THE CWA TOMORROW...BRINGING COOLER TEMPERATURES AND DRY
CONDITIONS.
THE CENTER OF THE HIGH WILL MOVE OFF TO THE EAST OF OUR CWA ON
SUNDAY...ALLOWING FOR RETURN SOUTHERLY FLOW TO DEVELOP WHICH WILL
IN TURN INITIATE WAA ACROSS THE UPPER MIDWEST. AS MOISTURE AND
TEMPS INCREASE ACROSS THE AREA...THE AIRMASS WILL DESTABILIZE
SUNDAY THRU TUESDAY. A COLD FRONT IS PROGGED TO PROPAGATE ACROSS
OUR CWA TUESDAY AND TUESDAY NIGHT...TAPPING THIS INCREASING
MOISTURE AND INSTABILITY...AND BRINGING ANOTHER ROUND OF SHOWERS
AND STORMS TO OUR FCST AREA.
HIGH TEMPERATURES WILL DROP 10 TO 20 DEGREES ACROSS THE NORTHLAND
BETWEEN TODAY TO TOMORROW. AS WINDS TURN OUT OF THE
NORTHEAST...THE COOLER TEMPS WILL ESPECIALLY BE NOTICEABLE ALONG
THE LAKE SUPERIOR SHORELINE.
AVIATION...ISOLD -SHRA/-TSRA WILL AFFECT MAINLY KDLH AND KHYR
THROUGH 21-23Z TIME FRAME AS AN UPPER LEVEL SHORT WAVE CROSSES THE
WESTERN GREAT LAKES. A COLD FRONT IS FORECAST TO MOVE THROUGH NE MN
THIS EVENING AND NW WI OVERNIGHT. LOOK FOR A WIND SHIFT TO THE NW
AFTER FROPA. BY 12Z SATURDAY...THE WIND WILL SWING AROUND TO THE NE
AS HIGH PRESSURE FROM CANADA BUILDS INTO THE AREA.
&&
POINT TEMPS/POPS...
DLH 50 58 44 62 / 20 10 10 20
INL 42 58 39 68 / 20 10 10 20
BRD 50 68 48 73 / 20 10 10 10
HYR 50 66 41 69 / 20 10 10 20
ASX 51 59 43 65 / 20 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
DAP
000
FXUS63 KMPX 192234 AAA
AFDMPX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
534 PM CDT FRI SEP 19 2008
.UPDATE...
UPDATED FOR 00Z AVIATION DISCUSSION BELOW.
&&
.DISCUSSION...
/ISSUED AT 144 PM CDT FRI SEP 19 2008/
WEAK FRONTAL BOUNDARY ALONG WITH SOME WEAK POSITIVE VORTICITY
ADVECTION WAS AIDING THE DEVELOPMENT OF SHRA/TSRA AHEAD OF THE FRONT
ACRS PORTIONS OF SOUTHERN MN INTO WESTERN WISCONSIN. THE LATEST IR
SATELLITE IMAGERY SHOWED A MINOR IMPLUSE OVR CNTRL MN...THIS WAVE
WAS ASLO HELPING WITH THE INITATION AND MAINTENANCE OF THE PRECIP.
THE IMPLUSE IS FORECAST TO MOVE EAST ACRS NORTHERN WI THIS EVENING.
WL KEEP SOME SMALL POPS GOING OVER THE SOUTHERN THIRD OF THE STATE
THIS EVENING.
ELSEWHERE...SKIES ARE EXPECTED TO CLEAR NORTH OF THE FRONTAL
BOUNDARY OVERNIGHT...WHILE SOME PATCHY CLOUDS OR BROKEN LAYER OCCURS
JUST SOUTH OF IT.
SATURDAY...WEAK FRONT STALLED OVER THE SOUTHERN THIRD OF THE
STATE...WILL BEGIN TO LIFT NORTH AS WARM FRONT LATE IN THE DAY. WL
GO ALONG WITH PREVIOUS FORECAST...A LEAVE SOME SMALL POPS IN
VICINITY OF THE FRONT.
MEDIUM RANGE IN GOOD AGREEMENT...WITH THE OVERALL UPPER AIR PATTERN
INTO THE NEXT WEEK. LONGWAVE UPPER RIDGE WILL SLOWLY BUILD AND MOVE
EAST OVER THE CENTRAL CONUS. MODERATE SUBSIDENCE ALOFT SHOULD KEEP
MOST AREAS DRY SATURDAY NIGHT INTO MONDAY MORNING.
BY MONDAY AFTERNOON...THE UPPER AIR PATTERN SHIFTS TO MORE
SOUTHWESTERLY AIRFLOW OVER THE MIDWEST WITH PRECIP CHANCES
INCREASING FROM WEST TO EAST OVER THE FORECAST AREA MONDAY INTO
TUESDAY. THE SHORT WAVE TROUGH FINALLY LIFTS EAST THROUGH OUR CWA
WEDNESDAY.
EXTENDED OUTLOOK...LTL CHANGE TO THE HPC GUIDANCE AND LEFT SOME POPS
TOWARD END OF NEW WORK WEEK. SHORTWAVE TROUGH FORECAST TO CARVE OUT
OVER THE UPPER MIDWEST...SATURDAY...LOOKS QUESTIONABLE...BY THE
LATEST GFS90 MODEL. FAST ZONAL FLOW OVER THE NORTHERN TIER U.S.
FORECAST CONFIDENCE IS SLOW.
&&
.AVIATION.../00Z TAF ISSUANCE/
VFR CONDS WL PREVAIL THRU THE VALID TAF PD. LEFT A VCSH DURG THE
FIRST FEW HRS OF THE TAF AT MSP AND RNH WITH RESIDUAL AFTN SHRA
REMAINING NEAR THOSE SITES. WINDS WL SHIFT TO A NERLY DIRN BEHIND
THE CDFNTL PASSAGE LATE TNGT...WITH SPDS REMAINING BLO 10 KTS DURG
THE AFTN TMRW.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JVM/KAT
000
FXUS63 KDLH 192056
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
356 PM CDT FRI SEP 19 2008
.DISCUSSION...LATEST KDLH RADAR IMAGERY SHOWS A LINE OF SCATTERED
SHOWERS AND THUNDERSTORMS EXTENDING ACROSS NORTHWESTERN WISCONSIN
AND PINE COUNTY THIS AFTERNOON. THIS ACTIVITY IS ASSOCIATED WITH
AN UPPER LEVEL SHORTWAVE DIGGING SE ACROSS THE AREA...PRECEDING
THE COLD FRONT WHICH IS JUST ENTERING THE NW CORNER OF OUR CWA.
THE PRECIPITATION WILL CONTINUE TO DISSIPATE THROUGH EARLY THIS
EVENING...AND END BY MIDNIGHT. THE COLD FRONT WILL TRACK SOUTHEAST
ACROSS OUR FCST AREA TONIGHT...EXITING TO THE SOUTH OF THE
NORTHLAND LATE TONIGHT. HIGH PRESSURE FROM CANADA WILL THEN BUILD
SOUTH OVER THE CWA TOMORROW...BRINGING COOLER TEMPERATURES AND DRY
CONDITIONS.
THE CENTER OF THE HIGH WILL MOVE OFF TO THE EAST OF OUR CWA ON
SUNDAY...ALLOWING FOR RETURN SOUTHERLY FLOW TO DEVELOP WHICH WILL
IN TURN INITIATE WAA ACROSS THE UPPER MIDWEST. AS MOISTURE AND
TEMPS INCREASE ACROSS THE AREA...THE AIRMASS WILL DESTABILIZE
SUNDAY THRU TUESDAY. A COLD FRONT IS PROGGED TO PROPAGATE ACROSS
OUR CWA TUESDAY AND TUESDAY NIGHT...TAPPING THIS INCREASING
MOISTURE AND INSTABILITY...AND BRINGING ANOTHER ROUND OF SHOWERS
AND STORMS TO OUR FCST AREA.
HIGH TEMPERATURES WILL DROP 10 TO 20 DEGREES ACROSS THE NORTHLAND
BETWEEN TODAY TO TOMORROW. AS WINDS TURN OUT OF THE
NORTHEAST...THE COOLER TEMPS WILL ESPECIALLY BE NOTICEABLE ALONG
THE LAKE SUPERIOR SHORELINE.
&&
.AVIATION...ISOLD -SHRA/-TSRA WILL AFFECT MAINLY KDLH AND KHYR
THROUGH 21-23Z TIME FRAME AS AN UPPER LEVEL SHORT WAVE CROSSES THE
WESTERN GREAT LAKES. A COLD FRONT IS FORECAST TO MOVE THROUGH NE MN
THIS EVENING AND NW WI OVERNIGHT. LOOK FOR A WIND SHIFT TO THE NW
AFTER FROPA. BY 12Z SATURDAY...THE WIND WILL SWING AROUND TO THE NE
AS HIGH PRESSURE FROM CANADA BUILDS INTO THE AREA.
&&
POINT TEMPS/POPS...
DLH 50 58 44 62 / 10 10 10 20
INL 42 58 39 68 / 10 10 10 20
BRD 50 68 48 73 / 10 10 10 10
HYR 50 66 41 69 / 20 10 10 20
ASX 51 59 43 65 / 10 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
BERDES/GSF
000
FXUS63 KMPX 191844
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
144 PM CDT FRI SEP 19 2008
.DISCUSSION...
WEAK FRONTAL BOUNDARY ALONG WITH SOME WEAK POSITIVE VORTICITY
ADVECTION WAS AIDING THE DEVELOPMENT OF SHRA/TSRA AHEAD OF THE FRONT
ACRS PORTIONS OF SOUTHERN MN INTO WESTERN WISCONSIN. THE LATEST IR
SATELLITE IMAGERY SHOWED A MINOR IMPLUSE OVR CNTRL MN...THIS WAVE
WAS ASLO HELPING WITH THE INITATION AND MAINTENANCE OF THE PRECIP.
THE IMPLUSE IS FORECAST TO MOVE EAST ACRS NORTHERN WI THIS EVENING.
WL KEEP SOME SMALL POPS GOING OVER THE SOUTHERN THIRD OF THE STATE
THIS EVENING.
ELSEWHERE...SKIES ARE EXPECTED TO CLEAR NORTH OF THE FRONTAL
BOUNDARY OVERNIGHT...WHILE SOME PATCHY CLOUDS OR BROKEN LAYER OCCURS
JUST SOUTH OF IT.
SATURDAY...WEAK FRONT STALLED OVER THE SOUTHERN THIRD OF THE
STATE...WILL BEGIN TO LIFT NORTH AS WARM FRONT LATE IN THE DAY. WL
GO ALONG WITH PREVIOUS FORECAST...A LEAVE SOME SMALL POPS IN
VICINITY OF THE FRONT.
MEDIUM RANGE IN GOOD AGREEMENT...WITH THE OVERALL UPPER AIR PATTERN
INTO THE NEXT WEEK. LONGWAVE UPPER RIDGE WILL SLOWLY BUILD AND MOVE
EAST OVER THE CENTRAL CONUS. MODERATE SUBSIDENCE ALOFT SHOULD KEEP
MOST AREAS DRY SATURDAY NIGHT INTO MONDAY MORNING.
BY MONDAY AFTERNOON...THE UPPER AIR PATTERN SHIFTS TO MORE
SOUTHWESTERLY AIRFLOW OVER THE MIDWEST WITH PRECIP CHANCES
INCREASING FROM WEST TO EAST OVER THE FORECAST AREA MONDAY INTO
TUESDAY. THE SHORT WAVE TROUGH FINALLY LIFTS EAST THROUGH OUR CWA
WEDNESDAY.
EXTENDED OUTLOOK...LTL CHANGE TO THE HPC GUIDANCE AND LEFT SOME POPS
TOWARD END OF NEW WORK WEEK. SHORTWAVE TROUGH FORECAST TO CARVE OUT
OVER THE UPPER MIDWEST...SATURDAY...LOOKS QUESTIONABLE...BY THE
LATEST GFS90 MODEL. FAST ZONAL FLOW OVER THE NORTHERN TIER U.S.
FORECAST CONFIDENCE IS SLOW.
&&
.AVIATION.../18Z TAF ISSUANCE/
SHOWERS WITH ISOLATED EMBEDDED THUNDERSTORMS CONTINUE TO
REGENERATE ACROSS WESTERN AND CENTRAL MINNESOTA IN RESPONSE TO A
STRETCHED OUT UPPER LEVEL DISTURBANCE WORKING ITS WAY EASTWARD.
ELEVATED INSTABILITY CONTINUES DUE TO STEEP MID-LEVEL LAPSE RATES.
HAVE HINTED AT SOME THUNDER IN STC AND RWF TAFS WITH THIS. LIKELY
TO HAVE THUNDER AT LEAST NEARBY STC DURING THE EARLY AFTN GIVEN
SAT AND RADAR TRENDS. AHEAD OF THE TROUGH...IN ERN MN AND WRN
WI...SWRLY WINDS CONTINUE TO BE GUSTY. AIDED BY CLEAR SKIES AND
GOOD MIXING...GUSTS IN EXCESS OF 20 KTS...POSSIBLY UP TO 25
KTS...ARE EXPECTED ALL AFTN AT WI SITES. TROUGH SHOULD WORK ITS
WAY EASTWARD THIS EVE...THOUGH DIFFERENTIAL TEMPERATURE ADVECTION
AND VORTICITY ADVECTION WEAKEN RAPIDLY...AND FORCING FOR SHOWERS
SEEMS MINIMAL. A SLIGHT CHANCE EXISTS FOR A COUPLE SHOWERS NEAR
MSP AND THE WI SITES BUT NOT TO THE DEGREE OF MENTION IN THE TAFS.
WINDS WILL BE SOMEWHAT VARIABLE TONIGHT TOO WITH THE TROUGH OOZING
THROUGH. SOME HIGH AND MID CLOUDS EXPECTED AT TIMES TOMORROW.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JVM/MTF
000
FXUS63 KMPX 191725
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1225 PM CDT FRI SEP 19 2008
.DISCUSSION...
PLENTY OF CONCERNS THIS MORNING WITH REGARDS TO THE FORECAST FOR
TODAY...TONIGHT AND SATURDAY. SHOWERS AND SOME THUNDERSTORMS
BECOMING MORE NUMEROUS JUST AHEAD OF A FRONTAL BOUNDARY FROM NW MN
THROUGH CENTRAL SD EARLY THIS MORNING. ACTIVITY LINES UP WELL WITH
THE 850-300MB THICKNESS RIDGE AND JUST LEFT OF A 40+ KNOT LOW
LEVEL JET. BOTH THE NCEP 4KM NMM WRF AND THE 4KM NSSL ARW WRF HAVE
A GOOD HANDLE ON THE ACTIVITY ATTM AND BRING SOME SHOWERS AND
THUNDERSTORMS IN THE NW CWA AROUND DAYBREAK. BOTH MODELS SHOW THE
ACTIVITY DIMINISHING LATE IN THE MORNING WHICH IS LIKELY TIED TO
LOW LEVEL MIXING AND WEAKENING OF THE LOW LEVEL JET. THERE IS ALSO
A LOSS IN THE 850MB MOISTURE TRANSPORT ACROSS CENTRAL MN AS WELL.
AS A RESULT...RAISED POPS INTO THE CHANCE CATEGORY FOR THE MORNING
ACROSS THE NW CWA.
THE BOUNDARY WILL BE SINKING SLOWLY SOUTH ACROSS THE CWA THIS
AFTERNOON AND TONIGHT. AGAIN..THE WRF`S ARE SHOWING SOME SPOTTY
THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING TO THE WEST
AND SOUTH OF HUTCHINSON. NAM SHOWING MOST UNSTABLE REACHING 1600
J/KG ALONG WITH BEST LI`S OF -4. LOW AND MID LEVEL LAPSE RATES ARE
BETWEEN 7 AND 8 DEG C/KM. HENCE...ADDED SOME SLIGHT CHANCE POPS
TO THE AFOREMENTIONED AREA AND KEPT THOSE ALREADY IN PLACE ACROSS
WEST CENTRAL WI FOR THE AFTERNOON AND EVENING. THE BOUNDARY
SHOULD BOTTOM OUT ALONG THE IA/MN BORDER ON SATURDAY AND AGAIN
MODEL SIGNALS...INCLUDING THE ECMWF...TRY SHOWING SOME PRECIP NEAR
THE IA BORDER LATE FRIDAY NIGHT AND SATURDAY MORNING.
ANOTHER PROBLEM TODAY AND AGAIN TOMORROW WILL BE HIGH TEMPERATURES.
ONCE AGAIN...THE MAV MOS WAS ON THE MARK YESTERDAY FOR HIGH
TEMPERATURES. BELIEVE TODAY WILL BE QUITE WARM WITH A LOW LEVEL
THERMAL RIDGE ACROSS THE CWA DURING THE AFTERNOON HOURS. NAM 850MB
TEMPERATURES ARE PROGGED TO RUN FROM +15 TO +18 DEG C FROM
LADYSMITH TO CANBY LATE THIS AFTERNOON. THIS IS ABOUT 2 DEGREES WARMER
OVER THE 19/00Z 850 MB ANAL. THEREFORE...PUSHED HIGHS JUST A
LITTLE ABOVE THURSDAY HIGHS WITH MIDDLE TO UPPER 80S FORECAST FOR
THE MN CWA AND LOWER 80S IN WI. ON SATURDAY...KEPT THE GRIDDED
HIGH TEMPERATURE FORECAST PRETTY MUCH THE WAY IT WAS. ETA MOS IS
ABOUT 10 DEGREES COOLER THAN THE MAV MOS...BUT THE LOW LEVEL
THERMAL GRADIENT DOESN`T SUPPORT THAT MUCH OF A DROP. IT WILL BE
COOLER...BUT LOWER 70S IN THE NORTHERN CWA TO UPPER 70S IN THE
SOUTHERN CWA ARE SUPPORTED BY THE NAM PROFILE DATA.
CHANCES FOR RAIN STILL IN THE FORECAST FOR THE WESTERN CWA ON
MONDAY AS A LEAD SHORT WAVE DAMPENS OUT IN THE RIDGE OVER THE WEST
GREAT LAKES. GFS/ECMWF IN PRETTY GOOD AGREEMENT ON SHOWING THE
BEST CHANCES OF PRECIP MONDAY NIGHT AND TUESDAY OVER THE NW CWA.
MAIN TROF ALOFT WILL BE SPREADING IN TUESDAY NIGHT AND WEDNESDAY
WITH A FRONTAL PASSAGE LIKELY ON WEDNESDAY. RAISED POPS OVER THE
WESTERN CWA TUESDAY NIGHT AS THE SURFACE FRONT MOVES IN LATE.
POPS WILL LIKELY HAVE TO BE RAISED FOR WEDNESDAY BY THE DAY
SHIFT...WHICH IS BEYOND ADJUSTMENT ON THE MIDNIGHT SHIFT.
&&
.AVIATION.../18Z TAF ISSUANCE/
SHOWERS WITH ISOLATED EMBEDDED THUNDERSTORMS CONTINUE TO
REGENERATE ACROSS WESTERN AND CENTRAL MINNESOTA IN RESPONSE TO A
STRETCHED OUT UPPER LEVEL DISTURBANCE WORKING ITS WAY EASTWARD.
ELEVATED INSTABILITY CONTINUES DUE TO STEEP MID-LEVEL LAPSE RATES.
HAVE HINTED AT SOME THUNDER IN STC AND RWF TAFS WITH THIS. LIKELY
TO HAVE THUNDER AT LEAST NEARBY STC DURING THE EARLY AFTN GIVEN
SAT AND RADAR TRENDS. AHEAD OF THE TROUGH...IN ERN MN AND WRN
WI...SWRLY WINDS CONTINUE TO BE GUSTY. AIDED BY CLEAR SKIES AND
GOOD MIXING...GUSTS IN EXCESS OF 20 KTS...POSSIBLY UP TO 25
KTS...ARE EXPECTED ALL AFTN AT WI SITES. TROUGH SHOULD WORK ITS
WAY EASTWARD THIS EVE...THOUGH DIFFERENTIAL TEMPERATURE ADVECTION
AND VORTICITY ADVECTION WEAKEN RAPIDLY...AND FORCING FOR SHOWERS
SEEMS MINIMAL. A SLIGHT CHANCE EXISTS FOR A COUPLE SHOWERS NEAR
MSP AND THE WI SITES BUT NOT TO THE DEGREE OF MENTION IN THE TAFS.
WINDS WILL BE SOMEWHAT VARIABLE TONIGHT TOO WITH THE TROUGH OOZING
THROUGH. SOME HIGH AND MID CLOUDS EXPECTED AT TIMES TOMORROW.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
RAH/MTF
000
FXUS63 KMPX 191050 AAA
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
550 AM CDT FRI SEP 19 2008
.UPDATED FOR AVIATION DISCUSSION BELOW...
.DISCUSSION...
PLENTY OF CONCERNS THIS MORNING WITH REGARDS TO THE FORECAST FOR
TODAY...TONIGHT AND SATURDAY. SHOWERS AND SOME THUNDERSTORMS
BECOMING MORE NUMEROUS JUST AHEAD OF A FRONTAL BOUNDARY FROM NW MN
THROUGH CENTRAL SD EARLY THIS MORNING. ACTIVITY LINES UP WELL WITH
THE 850-300MB THICKNESS RIDGE AND JUST LEFT OF A 40+ KNOT LOW
LEVEL JET. BOTH THE NCEP 4KM NMM WRF AND THE 4KM NSSL ARW WRF HAVE
A GOOD HANDLE ON THE ACTIVITY ATTM AND BRING SOME SHOWERS AND
THUNDERSTORMS IN THE NW CWA AROUND DAYBREAK. BOTH MODELS SHOW THE
ACTIVITY DIMINISHING LATE IN THE MORNING WHICH IS LIKELY TIED TO
LOW LEVEL MIXING AND WEAKENING OF THE LOW LEVEL JET. THERE IS ALSO
A LOSS IN THE 850MB MOISTURE TRANSPORT ACROSS CENTRAL MN AS WELL.
AS A RESULT...RAISED POPS INTO THE CHANCE CATEGORY FOR THE MORNING
ACROSS THE NW CWA.
THE BOUNDARY WILL BE SINKING SLOWLY SOUTH ACROSS THE CWA THIS
AFTERNOON AND TONIGHT. AGAIN..THE WRF`S ARE SHOWING SOME SPOTTY
THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING TO THE WEST
AND SOUTH OF HUTCHINSON. NAM SHOWING MOST UNSTABLE REACHING 1600
J/KG ALONG WITH BEST LI`S OF -4. LOW AND MID LEVEL LAPSE RATES ARE
BETWEEN 7 AND 8 DEG C/KM. HENCE...ADDED SOME SLIGHT CHANCE POPS
TO THE AFOREMENTIONED AREA AND KEPT THOSE ALREADY IN PLACE ACROSS
WEST CENTRAL WI FOR THE AFTERNOON AND EVENING. THE BOUNDARY
SHOULD BOTTOM OUT ALONG THE IA/MN BORDER ON SATURDAY AND AGAIN
MODEL SIGNALS...INCLUDING THE ECMWF...TRY SHOWING SOME PRECIP NEAR
THE IA BORDER LATE FRIDAY NIGHT AND SATURDAY MORNING.
ANOTHER PROBLEM TODAY AND AGAIN TOMORROW WILL BE HIGH TEMPERATURES.
ONCE AGAIN...THE MAV MOS WAS ON THE MARK YESTERDAY FOR HIGH
TEMPERATURES. BELIEVE TODAY WILL BE QUITE WARM WITH A LOW LEVEL
THERMAL RIDGE ACROSS THE CWA DURING THE AFTERNOON HOURS. NAM 850MB
TEMPERATURES ARE PROGGED TO RUN FROM +15 TO +18 DEG C FROM
LADYSMITH TO CANBY LATE THIS AFTERNOON. THIS IS ABOUT 2 DEGREES WARMER
OVER THE 19/00Z 850 MB ANAL. THEREFORE...PUSHED HIGHS JUST A
LITTLE ABOVE THURSDAY HIGHS WITH MIDDLE TO UPPER 80S FORECAST FOR
THE MN CWA AND LOWER 80S IN WI. ON SATURDAY...KEPT THE GRIDDED
HIGH TEMPERATURE FORECAST PRETTY MUCH THE WAY IT WAS. ETA MOS IS
ABOUT 10 DEGREES COOLER THAN THE MAV MOS...BUT THE LOW LEVEL
THERMAL GRADIENT DOESN`T SUPPORT THAT MUCH OF A DROP. IT WILL BE
COOLER...BUT LOWER 70S IN THE NORTHERN CWA TO UPPER 70S IN THE
SOUTHERN CWA ARE SUPPORTED BY THE NAM PROFILE DATA.
CHANCES FOR RAIN STILL IN THE FORECAST FOR THE WESTERN CWA ON
MONDAY AS A LEAD SHORT WAVE DAMPENS OUT IN THE RIDGE OVER THE WEST
GREAT LAKES. GFS/ECMWF IN PRETTY GOOD AGREEMENT ON SHOWING THE
BEST CHANCES OF PRECIP MONDAY NIGHT AND TUESDAY OVER THE NW CWA.
MAIN TROF ALOFT WILL BE SPREADING IN TUESDAY NIGHT AND WEDNESDAY
WITH A FRONTAL PASSAGE LIKELY ON WEDNESDAY. RAISED POPS OVER THE
WESTERN CWA TUESDAY NIGHT AS THE SURFACE FRONT MOVES IN LATE.
POPS WILL LIKELY HAVE TO BE RAISED FOR WEDNESDAY BY THE DAY
SHIFT...WHICH IS BEYOND ADJUSTMENT ON THE MIDNIGHT SHIFT.
&&
.AVIATION... /12Z TAF ISSUANCE/
APPEARS VFR CONDS SHUD PREVAIL THRU THE PD. FNTL BNDRY WL DROP SWRD
ACRS SITES FM LT MRNG THRU THE AFTN AND EVE HRS. WDLY SCT SHRA/TSRA
WL AFFECT WC MN THIS MORNING...AND WILL MENTION TEMP SHRA THERE
THROUGH ABOUT 14Z. ACTIVITY WL WANE SOME...THEN WITH HEATING AND
WEAK FORCING/CONVERGENCE ALONG BNDRY...COULD SEE MORE ISOLD ACTIVITY
DEVELOP AFTER 19Z. WILL MENTION VCSH AT KRNH/KRWF AREAS THIS
AFTERNOON FOR THIS POSSIBILITY. SOME GUSTY SSWRLY WINDS WL DEVELOP
ACRS THE SITES...BUT WL DECR TO ARND 5 KTS AFT SUNSET. THEN AS SFC
BNDRY DROPS SOUTH...WINDS WILL BECOME MORE NELY.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
RAH/DWE
000
FXUS63 KDLH 190859
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
359 AM CDT FRI SEP 19 2008
.DISCUSSION...
CURRENT SURFACE ANALYSIS SHOWS A DEEPENING 995 MB LOW PRESSURE
SYSTEM OVER THE NORTHERN MANITOBA WITH AN ASSOCIATED STRONG COLD
FRONT...CONTINUING ITS MIGRATION OFF TO THE SOUTH AND EAST. A SURFACE
TROUGH EXTENDS SOUTH AND WEST TO A SERIES OF WEAK SURFACE LOWS
EXTENDING THROUGH THE NORTHERN PLAINS INTO EASTERN COLORADO. THE CWA
STILL REMAINS IN THE GRADIENT BETWEEN THIS DEEPENING LOW...AND A
STRONG HIGH NOW WELL INTO THE NORTHEAST UNITED STATES. WARM AIR
ADVECTION COUPLED WITH A STRONG LOW LEVEL JET UPWARDS OF 45 TO 50
KNOTS AT 500 METERS ACROSS WESTERN MINNESOTA...AND A SW TO NE
ORIENTED THETA-E AXIS...IS LEADING TO SOME SCATTERED CONVECTION IN
THE EASTERN DAKOTAS AND WESTERN MINNESOTA. SO FAR...THE DULUTH CWA
HAS SEEN SOME MID CLOUDS AND SOME LIGHT DRIZZLE...THOUGH CONVECTION
IS OCCURRING OFF TO THE WEST.
THIS INCREASING LLJ IMPINGING ON A STRONG 950-700MB THERMAL
BOUNDARY...COUPLED WITH SOME WEAK TO MODEST INSTABILITY...WILL LEAD
TO ISOLATED THUNDERSTORMS OVER THE NORTHLAND TODAY. HAVE LEFT THE
WORDING AS ISOLATED SINCE BUFR SOUNDINGS CONTINUE TO SHOW RATHER DRY
AIR IN PLACE...WHICH WILL LIMIT THE AREAL COVERAGE OF STORMS.
COVERAGE SHOULD BE HIGHER THAN THURSDAY MORNING WITH SOME MODEST LO
TO MID LEVEL MOISTURE TRANSPORT...COUPLED WITH THE EASTWARD MOVING
BOUNDARY PROVIDED BY THE SURFACE TROUGH EXTENSION OF THE CANADIAN
LOW. WARM AIR ADVECTION WILL CONTINUE ON FRIDAY WITH SOUTHERLY
FLOW AHEAD OF THE APPROACHING FRONT...WARMING TEMPERATURES ACROSS
THE NORTHLAND INTO THE UPPER 70S AND LOW 80S...AND CONDITIONS WILL
BE BREEZY AGAIN.
ON FRIDAY NIGHT...THE RELATIVELY DRY FRONTAL BOUNDARY THAT IS
CURRENTLY NORTH OF THE BORDER WILL RAPIDLY DIVE SOUTHEASTWARD.
BEHIND THE COLD FRONT...A DOME OF COLD AND DRY AIR WILL ADVECT INTO
THE NORTHERN PLAINS AND UPPER MIDWEST...BRINGING A QUICK TASTE OF
AUTUMN. A TRICKY TEMPERATURE FORECAST IS SHAPING UP FOR FRIDAY
NIGHT AND SATURDAY. MET GUIDANCE IS QUITE COOLER ON FRIDAY
NIGHT...WITH STRONG HEIGHT AND THICKNESS FALLS...EVEN THOUGH THE
GFS/NAM AGREE RATHER WELL AS TO THE TIMING OF THE PASSAGE OF THE
FRONT. THE FRONT IS PROGGED TO CLEAR THE INTERNATIONAL BORDER
BETWEEN 21Z AND 0Z FRIDAY...REACHING THE TWIN PORTS AROUND 3Z...AND
CLEARING THE ENTIRE CWA BY 6Z SATURDAY. HAVE TRENDED SLIGHTLY COOLER
THAN THE MAV GUIDANCE...WHICH TRENDED DOWN FROM ONGOING
FORECAST...THOUGH TEMPS IN THE NORTH MAY NOT BE LOW ENOUGH...WITH
THE MET GOING FOR 38 AT INTERNATIONAL FALLS. MET GUIDANCE FOR
OVERNIGHT LOW TEMPERATURES SATURDAY MORNING IS ANYWHERE FROM 5 TO
EVEN 10 DEGREES BELOW MAV GUIDANCE...AND A SIMILAR TREND IS FOUND FOR
HIGH TEMPERATURES ON SATURDAY. EITHER WAY...IT WILL BE COOL AND A
BIT BREEZY...AS HIGH PRESSURE SINKS IN...AND WINDS SHIFT TO
NORTHERLY AND NORTHEASTERLY.
WITH THE HIGH PRESSURE SINKING SOUTH TOWARDS THE LAKE...RETURN FLOW
WILL SET UP AGAIN QUICKLY ON SUNDAY...AND A WARMING TREND WILL AGAIN
ENSUE. A WET PATTERN RETURNS FOR NEXT AS SERIES OF WAVES MOVE
THROUGH THE NORTHLAND.
&&
.AVIATION...
VFR CONDS EXPECTED THRU TAF PD. SCT-BKN MID CLDS WILL PERSIST THRU
THE EARLY AFTN HRS AS A WEAK CFNT MOVES THRU THE AREA. WINDS WILL
VEER FROM SW TO N DURING THE DAY AS THE FNT PASSES AND HIGH PRESS
SETTLES IN FROM THE N. ONLY AN ISOLD SHRA OR TSTM EXPECTED WITH THE
FNT. LLWS PSBL THIS MRNG UNTIL SFC BASED TEMP INVRN ERODES AND SFC
WINDS INCRS.
&&
POINT TEMPS/POPS...
DLH 79 51 58 41 / 20 10 10 10
INL 78 43 57 39 / 20 10 10 10
BRD 82 51 69 51 / 20 10 10 10
HYR 80 52 66 40 / 20 10 10 10
ASX 81 53 59 42 / 20 10 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
LSZ140-LSZ141-LSZ142-LSZ143-LSZ144-LSZ145-LSZ146-LSZ147-
LSZ148.
$$
DONOFRIO/04
000
FXUS63 KMPX 190825
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
325 AM CDT FRI SEP 19 2008
.DISCUSSION...
PLENTY OF CONCERNS THIS MORNING WITH REGARDS TO THE FORECAST FOR
TODAY...TONIGHT AND SATURDAY. SHOWERS AND SOME THUNDERSTORMS
BECOMING MORE NUMEROUS JUST AHEAD OF A FRONTAL BOUNDARY FROM NW MN
THROUGH CENTRAL SD EARLY THIS MORNING. ACTIVITY LINES UP WELL WITH
THE 850-300MB THICKNESS RIDGE AND JUST LEFT OF A 40+ KNOT LOW
LEVEL JET. BOTH THE NCEP 4KM NMM WRF AND THE 4KM NSSL ARW WRF HAVE
A GOOD HANDLE ON THE ACTIVITY ATTM AND BRING SOME SHOWERS AND
THUNDERSTORMS IN THE NW CWA AROUND DAYBREAK. BOTH MODELS SHOW THE
ACTIVITY DIMINISHING LATE IN THE MORNING WHICH IS LIKELY TIED TO
LOW LEVEL MIXING AND WEAKENING OF THE LOW LEVEL JET. THERE IS ALSO
A LOSS IN THE 850MB MOISTURE TRANSPORT ACROSS CENTRAL MN AS WELL.
AS A RESULT...RAISED POPS INTO THE CHANCE CATEGORY FOR THE MORNING
ACROSS THE NW CWA.
THE BOUNDARY WILL BE SINKING SLOWLY SOUTH ACROSS THE CWA THIS
AFTERNOON AND TONIGHT. AGAIN..THE WRF`S ARE SHOWING SOME SPOTTY
THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING TO THE WEST
AND SOUTH OF HUTCHINSON. NAM SHOWING MOST UNSTABLE REACHING 1600
J/KG ALONG WITH BEST LI`S OF -4. LOW AND MID LEVEL LAPSE RATES ARE
BETWEEN 7 AND 8 DEG C/KM. HENCE...ADDED SOME SLIGHT CHANCE POPS
TO THE AFOREMENTIONED AREA AND KEPT THOSE ALREADY IN PLACE ACROSS
WEST CENTRAL WI FOR THE AFTERNOON AND EVENING. THE BOUNDARY
SHOULD BOTTOM OUT ALONG THE IA/MN BORDER ON SATURDAY AND AGAIN
MODEL SIGNALS...INCLUDING THE ECMWF...TRY SHOWING SOME PRECIP NEAR
THE IA BORDER LATE FRIDAY NIGHT AND SATURDAY MORNING.
ANOTHER PROBLEM TODAY AND AGAIN TOMORROW WILL BE HIGH TEMPERATURES.
ONCE AGAIN...THE MAV MOS WAS ON THE MARK YESTERDAY FOR HIGH
TEMPERATURES. BELIEVE TODAY WILL BE QUITE WARM WITH A LOW LEVEL
THERMAL RIDGE ACROSS THE CWA DURING THE AFTERNOON HOURS. NAM 850MB
TEMPERATURES ARE PROGGED TO RUN FROM +15 TO +18 DEG C FROM
LADYSMITH TO CANBY LATE THIS AFTERNOON. THIS IS ABOUT 2 DEGREES WARMER
OVER THE 19/00Z 850 MB ANAL. THEREFORE...PUSHED HIGHS JUST A
LITTLE ABOVE THURSDAY HIGHS WITH MIDDLE TO UPPER 80S FORECAST FOR
THE MN CWA AND LOWER 80S IN WI. ON SATURDAY...KEPT THE GRIDDED
HIGH TEMPERATURE FORECAST PRETTY MUCH THE WAY IT WAS. ETA MOS IS
ABOUT 10 DEGREES COOLER THAN THE MAV MOS...BUT THE LOW LEVEL
THERMAL GRADIENT DOESN`T SUPPORT THAT MUCH OF A DROP. IT WILL BE
COOLER...BUT LOWER 70S IN THE NORTHERN CWA TO UPPER 70S IN THE
SOUTHERN CWA ARE SUPPORTED BY THE NAM PROFILE DATA.
CHANCES FOR RAIN STILL IN THE FORECAST FOR THE WESTERN CWA ON
MONDAY AS A LEAD SHORT WAVE DAMPENS OUT IN THE RIDGE OVER THE WEST
GREAT LAKES. GFS/ECMWF IN PRETTY GOOD AGREEMENT ON SHOWING THE
BEST CHANCES OF PRECIP MONDAY NIGHT AND TUESDAY OVER THE NW CWA.
MAIN TROF ALOFT WILL BE SPREADING IN TUESDAY NIGHT AND WEDNESDAY
WITH A FRONTAL PASSAGE LIKELY ON WEDNESDAY. RAISED POPS OVER THE
WESTERN CWA TUESDAY NIGHT AS THE SURFACE FRONT MOVES IN LATE.
POPS WILL LIKELY HAVE TO BE RAISED FOR WEDNESDAY BY THE DAY
SHIFT...WHICH IS BEYOND ADJUSTMENT ON THE MIDNIGHT SHIFT.
&&
.AVIATION... /06Z TAF ISSUANCE/
VFR CONDS SHUD PREVAIL THRU THE PD. FNTL BNDRY WL DROP SWRD ACRS
THE SITES FM LT MRNG THRU THE AFTN AND EVE HRS. COULD BE SOME
ISOLD SHRA/TSRA ACRS THE CWFA AS A WHOLE...BUT CONFIDENCE AT ANY
ONE TAF SITE IS NOT GREAT ENUF TO MENTION ATTM. GUSTY SSWRLY WINDS
WL DEVELOP ACRS THE SITES DURG THE AFTN...DECR TO ARND 5 KTS AFT
SUNSET.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
RAH/KAT
000
FXUS63 KMPX 190317 AAA
AFDMPX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1017 PM CDT THU SEP 18 2008
.UPDATE...
UPDATED FOR 06Z AVIATION DISCUSSION BELOW.
&&
.DISCUSSION...
/ISSUED AT 316 PM CDT THU SEP 18 2008/
MOD TO STRONG SSW FLOW WILL CONTINUE THIS EVENING AHEAD OF THE LOW
PRESSURE TROUGH OVER THE CENTRAL DAKOTAS. DECENT DIFFERENTIAL TEMP
ADVECTION DEVELOPS OVER THE EASTERN DAKOTAS INTO WEST CENTRAL MN
LATE TONIGHT AND FRIDAY MORNING BUT HIGHER K INDICES DO NOT WORK
INTO CENTRAL MN UNTIL FRIDAY. SOME ELEVATED CAPE SHOWING UP IN
THE FORECAST SOUNDINGS. UPPER AIR SUPPORT ON THE WEAK SIDE THOUGH.
WILL HOWEVER INTRODUCE A SMALL POP ON FRIDAY IN NORTH CWA AS
BETTER LOW LEVEL MOISTURE TRANSPORT COINCIDES WITH HIGHER K
INDICES. SREF POPS MAXIMIZE IN THIS AREA AS WELL. WILL ALSO KEEP
THE SMALL POP OVER WEST CENTRAL WI FRIDAY NIGHT AS THE FRONT
TRAILS OFF. NEGATIVE FACTOR WILL BE AN INITIAL CAP. SHOULD BE A
WARM DAY AHEAD OF THE FRONT AND 80S COMMON MOST LOCATIONS. CAN`T
RULE OUT A COUPLE UPPER 80S KCNB...KDXX AREA...SIMILAR TO TUESDAY.
THE BOUNDARY WILL RETREAT TO THE NORTH AGAIN SATURDAY AND SATURDAY
NIGHT. THERE IS SOME RISK OF PRECIP BUT THE TEMP GRADIENT WILL
DEVELOP MORE OVER NORTHEAST MN. WILL LEAVE OUT AT THIS TIME BU
THE BEST CHANCE WOULD BE OVER CENTRAL MN.
NEXT BEST PRECIP CHANCES STILL APPEAR TO BE MID WEEK. BEST
INCREASE IN GFS ENSEMBLE POPS IS ON WED. THERE IS UNCERTAINTY IN
THE SPEED AND INTENSITY OF THE UPPER TROUGH IN THE WEST AS RIDGE
BUILDS IN THE EAST...ALONG WITH A SPLIT POTENTIAL TO OUR SOUTH.
WILL KEEP SOME POPS IN THROUGH WEDNESDAY NIGHT AND THURSDAY BUT
LESSER CHANCES ON THURSDAY.
&&
.AVIATION.../06Z TAF ISSUANCE/
VFR CONDS SHUD PREVAIL THRU THE PD. FNTL BNDRY WL DROP SWRD ACRS
THE SITES FM LT MRNG THRU THE AFTN AND EVE HRS. COULD BE SOME
ISOLD SHRA/TSRA ACRS THE CWFA AS A WHOLE...BUT CONFIDENCE AT ANY
ONE TAF SITE IS NOT GREAT ENUF TO MENTION ATTM. GUSTY SSWRLY WINDS
WL DEVELOP ACRS THE SITES DURG THE AFTN...DECR TO ARND 5 KTS AFT
SUNSET.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JPR/KAT
000
FXUS63 KMPX 182333 AAA
AFDMPX
AREA FORECAST DISCUSSION...UPDATED FOR 00Z TAF
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
630 PM CDT THU SEP 18 2008
.DISCUSSION...ISSUED 316 PM CDT
MOD TO STRONG SSW FLOW WILL CONTINUE THIS EVENING AHEAD OF THE LOW
PRESSURE TROUGH OVER THE CENTRAL DAKOTAS. DECENT DIFFERENTIAL TEMP
ADVECTION DEVELOPS OVER THE EASTERN DAKOTAS INTO WEST CENTRAL MN
LATE TONIGHT AND FRIDAY MORNING BUT HIGHER K INDICES DO NOT WORK
INTO CENTRAL MN UNTIL FRIDAY. SOME ELEVATED CAPE SHOWING UP IN
THE FORECAST SOUNDINGS. UPPER AIR SUPPORT ON THE WEAK SIDE THOUGH.
WILL HOWEVER INTRODUCE A SMALL POP ON FRIDAY IN NORTH CWA AS
BETTER LOW LEVEL MOISTURE TRANSPORT COINCIDES WITH HIGHER K
INDICES. SREF POPS MAXIMIZE IN THIS AREA AS WELL. WILL ALSO KEEP
THE SMALL POP OVER WEST CENTRAL WI FRIDAY NIGHT AS THE FRONT
TRAILS OFF. NEGATIVE FACTOR WILL BE AN INITIAL CAP. SHOULD BE A
WARM DAY AHEAD OF THE FRONT AND 80S COMMON MOST LOCATIONS. CAN`T
RULE OUT A COUPLE UPPER 80S KCNB...KDXX AREA...SIMILAR TO TUESDAY.
THE BOUNDARY WILL RETREAT TO THE NORTH AGAIN SATURDAY AND SATURDAY
NIGHT. THERE IS SOME RISK OF PRECIP BUT THE TEMP GRADIENT WILL
DEVELOP MORE OVER NORTHEAST MN. WILL LEAVE OUT AT THIS TIME BU
THE BEST CHANCE WOULD BE OVER CENTRAL MN.
NEXT BEST PRECIP CHANCES STILL APPEAR TO BE MID WEEK. BEST
INCREASE IN GFS ENSEMBLE POPS IS ON WED. THERE IS UNCERTAINTY IN
THE SPEED AND INTENSITY OF THE UPPER TROUGH IN THE WEST AS RIDGE
BUILDS IN THE EAST...ALONG WITH A SPLIT POTENTIAL TO OUR SOUTH.
WILL KEEP SOME POPS IN THROUGH WEDNESDAY NIGHT AND THURSDAY BUT
LESSER CHANCES ON THURSDAY.
&&
.AVIATION.../00Z TAF ISSUANCE/
XPCT SM DECPLNG OF WND FIELD IN NEXT CUPL HRS WHICH WL LIMIT THE
GUSTS...BUT ENUF GRADIENT FOR SUSTAINED 10 TO 15 KT WNDS THRU NITE
XCPT PERHAPS AT WI SITES. CONTD WITH MENTION OF PROB30 AT AXN AND
STC FRI MRNG AS WK UPR TROF APRCHS AND PROVIDES SM FORCING. SFC FNT
APRCHS AXN/STC BY 00Z...BUT ATTM CIN LKS RATHER STG SO WL NOT INTRO
PCPN.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JPR/BAP
000
FXUS63 KDLH 182025
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
325 PM CDT THU SEP 18 2008
.DISCUSSION...
CURRENT SFC ANALYSIS SHOWS A STRONG PRESSURE GRADIENT OVER THE
REGION PRODUCING GUSTY SRLY WINDS AND MOSTLY CLR SKIES. EXCEPT OVER LK
SUPERIOR WHERE GENERALLY E TO NE WINDS 5-10 KTS ARE FOUND.
AFT 03Z...SRLY LO LVL WINDS INCREASE RAPIDLY AS THE JET AXIS SHIFTS
E OVER THE FA. ALTHOUGH THE NAM IS QUITE A BIT STRONGER /40-50 KT
AT 925 MB/ THAN THE GFS /30-40 KT/...IN EITHER CASE THERE WILL BE
INCREASING INSTABILITY AND MOISTURE TO ALLOW FOR FEW SHRA OR TSRA
TO DEVELOP ON THE NOSE OF THE WAA AHEAD OF APPROACHING COLD FRONT.
HOWEVER...DRY AIR DEPICTED ON BUFR SOUNDINGS WILL LIMIT THE AREAL
COVERAGE AND PCPN AMOUNTS...SO KEPT ISOLD WORDING AND 20S POPS
ATTM. ONLY MINOR ADJUSTMENTS TO PLACING/TIMING OF SMALL POPS TO
REFLECT FROPA ON FRI/FRI NIGHT.
A HUDSON BAY HIGH WILL SINK INTO THE REGION BEHIND THE COLD FRONT
LATE FRIDAY...LINGERING THROUGH THE WEEKEND. THIS FEATURE WILL
BRING IMPRESSIVE THICKNESS AND HEIGHT FALLS AS WELL AS COOLER
TEMPERATURES. HOWEVER...COOL DOWN WILL BE SHORT LIVED AS UPR LVL
RIDGE BUILDS OVR THE HIGH PLAINS BRINGING A RETURN FLOW AND
REBOUNDING TEMPERATURE.
&&
.AVIATION...
VFR CONDS WL PVL ACRS MST OF THE AREA DURG THE NXT 48
HRS. IFR CONDS IN ISOLD TSTMS WL BE ALG THE CANADIAN BRDR THRU THIS
EVE...N OF DLH TNGT...AND S AND W OF THE IRON RANGE FRI.
&&
POINT TEMPS/POPS...
DLH 58 80 54 60 / 20 20 10 10
INL 55 78 48 61 / 20 10 10 10
BRD 57 81 54 72 / 20 20 10 10
HYR 58 80 55 68 / 10 20 10 10
ASX 57 81 55 61 / 10 20 20 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 PM CDT FRIDAY
FOR LSZ121-LSZ140-LSZ141-LSZ142-LSZ143-LSZ144-LSZ145-LSZ146-
LSZ147-LSZ148.
$$
GRANING/EOM
000
FXUS63 KMPX 182016
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
316 PM CDT THU SEP 18 2008
.DISCUSSION...
MOD TO STRONG SSW FLOW WILL CONTINUE THIS EVENING AHEAD OF THE LOW
PRESSURE TROUGH OVER THE CENTRAL DAKOTAS. DECENT DIFFERENTIAL TEMP
ADVECTION DEVELOPS OVER THE EASTERN DAKOTAS INTO WEST CENTRAL MN
LATE TONIGHT AND FRIDAY MORNING BUT HIGHER K INDICES DO NOT WORK
INTO CENTRAL MN UNTIL FRIDAY. SOME ELEVATED CAPE SHOWING UP IN
THE FORECAST SOUNDINGS. UPPER AIR SUPPORT ON THE WEAK SIDE THOUGH.
WILL HOWEVER INTRODUCE A SMALL POP ON FRIDAY IN NORTH CWA AS
BETTER LOW LEVEL MOISTURE TRANSPORT COINCIDES WITH HIGHER K
INDICES. SREF POPS MAXIMIZE IN THIS AREA AS WELL. WILL ALSO KEEP
THE SMALL POP OVER WEST CENTRAL WI FRIDAY NIGHT AS THE FRONT
TRAILS OFF. NEGATIVE FACTOR WILL BE AN INITIAL CAP. SHOULD BE A
WARM DAY AHEAD OF THE FRONT AND 80S COMMON MOST LOCATIONS. CAN`T
RULE OUT A COUPLE UPPER 80S KCNB...KDXX AREA...SIMILAR TO TUESDAY.
THE BOUNDARY WILL RETREAT TO THE NORTH AGAIN SATURDAY AND SATURDAY
NIGHT. THERE IS SOME RISK OF PRECIP BUT THE TEMP GRADIENT WILL
DEVELOP MORE OVER NORTHEAST MN. WILL LEAVE OUT AT THIS TIME BU
THE BEST CHANCE WOULD BE OVER CENTRAL MN.
NEXT BEST PRECIP CHANCES STILL APPEAR TO BE MID WEEK. BEST
INCREASE IN GFS ENSEMBLE POPS IS ON WED. THERE IS UNCERTAINTY IN
THE SPEED AND INTENSITY OF THE UPPER TROUGH IN THE WEST AS RIDGE
BUILDS IN THE EAST...ALONG WITH A SPLIT POTENTIAL TO OUR SOUTH.
WILL KEEP SOME POPS IN THROUGH WEDNESDAY NIGHT AND THURSDAY BUT
LESSER CHANCES ON THURSDAY.
&&
.AVIATION.../18Z TAF ISSUANCE/
BREEZY SOUTHERLY WINDS DEVELOPING ACROSS MUCH OF THE REGION THIS
AFTN AS SURFACE PRESSURE GRADIENT TIGHTENS AND MOSTLY SUNNY SKIES
HAVE ALLOWED FOR FULL MIXING TO ESTABLISH ITSELF. GOING SUSTAINED
WINDS AND GUSTS IN TAF LOOK GOOD FOR THIS AFTN GIVEN OBSERVATIONAL
TRENDS AND RUC PREDICTIONS OF MIXING HEIGHTS. WOOD LAKE PROFILER
SHOWING 40 KTS AT 1-2 KFT...SO GUSTS OF 75 TO 80 PERCENT OF THAT
/OR NEAR 30 KTS/ ARE EXPECTED AT AXN AND RWF. MPX VAD PROFILER
REVEALS LESS SPEEDS...BUT STILL 20-25 KTS AT 2-4 KFT...WELL WITHIN
THE MIXING LAYER. SOME REGENERATING 6-8 KFT CLOUDS EXPECTED ON
GRADUALLY MOISTENING WARM AIR ADVECTION IN THAT LAYER. SFC WINDS
TO LOSE THEIR GUSTS TONIGHT WHILE SUSTAINED STAY UP IN THE 10-14
KT CATEGORY. WEAK SFC TROUGH TO MOVE INTO WRN MN JUST PRIOR TO
DAYBREAK TOMORROW. SOME SCT LIGHT SHOWERS ALONG OR BEHIND THIS
SEEM POSSIBLE WITH MARGINAL LAPSE RATES AND ASSOCIATED ELEVATED
INSTABILITY ENOUGH TO KEEP THEM ALIVE AS THEY HEAD EAST FROM
ND/SD. HAVE A PROB GROUP AT AXN TO ACCOUNT FOR THIS CONFIDENCE.
SEEMS LIKE A SMALL CHANCE FOR A SHOWER JUST BEYOND TAF
PERIOD...FRI AFTN AND EVE...ACROSS OTHER TAF SITES DUE TO THIS
TROUGH PASSAGE. MAY NOT BE WORTH MENTION THOUGH AT 00Z.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JPR/MTF
000
FXUS63 KMPX 181056 AAA
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
556 AM CDT THU SEP 18 2008
.UPDATED FOR AVIATION DISCUSSION BELOW...
.DISCUSSION...
HIGH PRESSURE CURRENTLY OVER THE UPPER GREAT LAKES WILL BE MOVING
EAST TODAY. PRESSURE GRADIENT ACROSS THE FA WILL TIGHTEN WITH
BREEZY SOUTH WINDS DEVELOPING. LOW LEVEL MOISTURE TRANSPORT AND
WAA MAXIMIZED TO OUR NORTH TODAY WITH BKN-OVC AC ALREADY COVERING
MUCH OF NORTHERN MN/WI...WITH SOME CLOUDINESS INTO RICE LAKE AND
LADYSMITH. 4KM NSSL WRF SHOWING SHOWERS AND THUNDERSTORMS
DEVELOPING LATE THIS MORNING OVER NW MN AND SPREADING EAST-
NORTHEAST DURING THE AFTERNOON. SOME VERY WEAK ECHOES ALSO NOTED
OVER EASTERN IA AND SE MN. THIS GOES ALONG WITH THE NAM/GFS
MOISTENING THE LOW LEVELS...SOME ISENTROPIC UPGLIDE ON THE 305K
THETA SURFACE AND A SHORT WAVE MOVING BY IN THE AFTERNOON.
MOISTURE IS BASICALLY CONFINED BETWEEN 800-900MB. LITTLE Q-VECTOR
FORCING FOUND ALOFT. KEPT THE FORECAST DRY BUT DID INCREASE CLOUD
COVER A LITTLE OVER THE EASTERN HALF OF THE CWA. PRESSURE GRADIENT
REMAINS OVER THE FA TONIGHT WITH A STEADY SOUTH WIND AND MILD
TEMPERATURES.
FRIDAY LOOKING RATHER WARM WITH AN 850MB THERMAL RIDGE RUNNING
WEST TO EAST ACROSS THE FA DURING THE AFTERNOON AHEAD OF AN
APPROACHING COLD FRONT. 850MB TEMPS PROGGED TO REACH 16 TO 19 DEG
C FROM KEAU TO KCNB. RAISED FORECAST HIGH TEMPS A FEW DEGREES. A
CANADIAN COLD FRONT WILL THEN SLIP SOUTH INTO THE FA FRIDAY NIGHT
AND BECOME STATIONARY OVER SOUTHERN MN AND ADJOINING AREAS OF WI
ON SATURDAY. A PRETTY MILD DAY STILL EXPECTED WITH THE LOW LEVEL
THERMAL RIBBON OVER SOUTHERN AREAS OF THE FA. SREF PRECIP
PROBABILITIES ESSENTIALLY NIL WITH DEEP LAYER MOISTURE AND FORCING
MINIMAL. KEPT SOME SMALL POPS NEAR THE KARX CWA FOR CONTINUITY.
SUNDAY THE PROCESS BEGINS ALL OVER AGAIN WITH THE BOUNDARY LIFTING
NORTH AND SOUTHERLY WINDS DEVELOPING AS ANOTHER SURFACE HIGH MOVES
EAST FROM THE UPPER GREAT LAKES. HOWEVER...THE CHANCES FOR RAIN WILL
BE ON THE INCREASE NEXT WEEK. THE 00Z GFS/ECMWF IN BETTER
AGREEMENT TONIGHT WITH THE GFS NOT AS DEEP ALOFT OVER THE PAST FEW
NIGHTS AS WELL AS BEING A LITTLE FASTER WITH THE TROF MOVING
ACROSS THE NORTHERN ROCKIES EARLY NEXT WEEK. A LEAD SHORT WAVE ON
BOTH SOLUTIONS DAMPENS OUT ON MONDAY OVER US WITH THE WESTERN CWA
HAVING SOME CHANCE FOR RAIN. CHANCES FOR RAIN INCREASING TUESDAY
AND WEDNESDAY AS THE TROF APPROACHES AND DEEPER MOISTURE INVADES
THE REGION.
&&
.AVIATION... /12Z TAF ISSUANCE/
VFR CONDITIONS WILL CONTINUE THRU PERIOD AS HI PRES MOVES ACROSS GRT
LKS REGION AND SELY FLOW INCRSS. SOME MID/HIGH LEVEL CLOUDS WILL
DRIFT OVER THE AREA...ASSOCIATED WITH WAA PATTERN. ALSO...MODELS
SUGGESTING A BIT MOVE CUMULUS POSSIBLE OVER EASTERN AREAS WITH
INCREASING CAPE PROGGED THIS AFTERNOON. WINDS SHOULD GUST TO 25 TO
30 KTS OVER FAR WESTERN MN DURING THE AFTERNOON...WITH GUSTS
DEVELOPING DURING THE AFTERNOON AS FAR EAST AS KEAU. WINDS WILL
DIMINISH SOME OVERNIGHT MOST AREAS...WITH AN INCREASE IN MID LEVEL
MOISTURE INDICATED OVER CENTRAL MN MAINLY AFTER 06Z FRI.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
RAH/DWE
000
FXUS63 KDLH 180843
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
343 AM CDT THU SEP 18 2008
.DISCUSSION...
...SHORT TERM...THURSDAY AND FRIDAY...
CURRENT SURFACE ANALYSIS SHOWS
STRENGTHENING 1030MB HIGH PRESSURE OVER THE NORTHERN TIP OF LAKE
SUPERIOR...CONTINUING ITS MIGRATION OFF TO THE SOUTH AND EAST. A
CLOSED SURFACE LOW PRESSURE IS CENTERED OVER SOUTHEAST
MONTANA...WITH THE CWA IN THE GRADIENT BETWEEN THESE TWO SYSTEMS.
WATER VAPOR IMAGERY DEPICTS A WEAK SHORTWAVE PROGRESSING
SOUTHEAST. VERY LITTLE PRECIP HAS BEEN REPORTED HITTING THE GROUND
UNTIL RECENTLY...AND MOST OF THE CLOUD BASES HAVE BEEN AROUND 9K-
12K FEET. WASKISH IS CURRENTLY REPORTING DRIZZLE AS OF 330 AM. AN
AREA OF STRATUS IS DEVELOPING ALONG THE NORTH SHORE...WITH WINDS
COMING OFF THE LAKE. WIND PROFILERS IN SOUTHWEST MINNESOTA DEPICT
500 METER WINDS OF 30 KNOTS OUT OF THE SOUTHEAST...WITH THE DULUTH
VAD WIND PROFILE SUGGESTING 22 KNOTS NOT TOO FAR OFF THE DECK.
THIS LOW LEVEL JET IS FORECAST TO INCREASE EARLY THIS MORNING AND VEER
SLIGHTLY TO BECOME SOUTH-SOUTHWESTERLY...AND CONTINUE TO REMAIN
STRONG THROUGHOUT THE DAY ON THURSDAY. THEN IT IS EXPECTED TO
STRENGTHEN EVEN FURTHER ON THURSDAY NIGHT INTO FRIDAY
MORNING...AND VEER TO BECOME WESTERLY BY FRIDAY 12Z. THE NAM12
INDICATES STRENGTHENING TO 50 TO 60 KNOTS AT 850 MB LATE THURSDAY
NIGHT INTO FRIDAY. WHILE VERY LITTLE PRECIPITATION IS HITTING THE
GROUND NOW...WITH THE INCREASING LLJ AND SOME WEAK INSTABILITY
AFTER 12Z...HAVE LEFT LOW POPS MAINLY IN THE IRON RANGE AND
ARROWHEAD THROUGH 18Z...BEFORE DIMINISHING BETWEEN 18Z AND
0Z...AND THEN AS THE LLJ STRENGTHENS OVERNIGHT THURSDAY INTO
FRIDAY...KEPT ONGOING FORECAST OF LOW POPS. FACTORS FAVORING TSRA
INCLUDE THE LLJ...WEAK ELEVATED INSTABILITY...THOUGH MOISTURE IS
LIMITED. THE GFS/ECMWF/HPC GIVE THE AREA PRECIP...WHILE THE SREF
IS DRY AND THE NAM...FOR THE MOST PART...IS DRY TOO. KEPT POPS
THROUGH FRIDAY 12Z...AND HAVE CURRENTLY KEPT THE ONGOING FORECAST
DRY AFTER 12Z...AS THE SREF AND MOST OF THE GFS ENSEMBLE MEMBERS
ARE DRY...THOUGH THE ECMWF WANTS TO KEEP THE PRECIP INTACT MOVING
SOUTH AND EAST INTO NW WISCONSIN. FUTURE FORECASTS WILL MONITOR
THIS...AS MOISTURE TRANSPORT INCREASES OVERNIGHT INTO FRIDAY.
WITH THE HIGH PRESSURE OVER LAKE SUPERIOR MAKING ITS SLOW EXIT AND
WITH THE APPROACHING LOW FROM MONTANA...THE CWA WILL REMAIN IN A
DECENT PRESSURE GRADIENT ON THURSDAY WITH A STRENGTHENING LOW IN
CENTRAL CANADA PROGGED TO PUSH EAST...AND GUSTY WINDS OF 15-20 MPH
CAN BE EXPECTED ACROSS MINNESOTA AND WESTERN PORTIONS OF NORTHWEST
WISCONSIN. DECENT MIXING IS EXPECTED...WHICH COULD BRING SOME
HIGHER GUSTS...ESPECIALLY IN THE WESTERN CWA. THE CWA WILL REMAIN
IN THE WARM ADVECTION REGIME...WITH 850 TEMPS WARMING TO 12-16 C
ON THURSDAY...16-19 C ON FRIDAY...SO EXPECT A DECENT WARMING TREND
THROUGH FRIDAY...BEFORE A COLD FRONT WILL PLUNGE SOUTH FRIDAY
NIGHT. THE FORECAST QUESTION FOR THE TWIN PORTS ON THURSDAY WILL
BE WHEN WINDS SHIFT TO MORE OF A SOUTHERLY DIRECTION...INSTEAD OF
SOUTHEAST. HAVE KEPT TEMPS COOLER IN THE TWIN PORTS AND ALONG THE
NORTH SHORE ON THURSDAY...WITH MOST AREAS WARMING NICELY ON FRIDAY
WITH SOUTH-SOUTHWESTERLY WINDS.
...LONG TERM...SATURDAY THROUGH WEDNESDAY...
HIGH PRESSURE SINKS IN SATURDAY TO SUNDAY...AND WINDS SHIFT TO
NORTHERLY AND NORTHEASTERLY OFF THE LAKE. CONDITIONS WILL BE
MARKEDLY COOLER...WITH HIGHS IN THE 60S OR COOLER...EXCEPT IN THE
FAR WEST. THERE IS LIMITED MOISTURE WITH THE FRONT...SO SKIES WILL
REMAIN PARTLY CLOUDY. A WET PATTERN RETURNS FOR NEXT WEEK AS
RETURN FLOW SETS UP...AND A SERIES OF WAVES MOVE THROUGH THE
NORTHLAND...AND PRECIPITABLE WATER VALUES INCREASE TO OVER AN INCH
TO NEAR 1.5 INCHES OVER THE AREA FOR THE EARLY HALF OF THE WEEK...WHICH
WILL BE 1 STANDARD DEVIATION ABOVE NORMAL FOR LATE
SEPTEMBER...BEFORE THE APPROACH OF ANOTHER FRONT MID WEEK.
&&
.AVIATION...
VFR CONDS EXPECTED THRU TAF PD. SCT-BKN MID CLDS WILL PERSIST THRU
THE MRNG HRS. ISOLD SHRA/TS PSBL THIS MRNG AS WELL...MAINLY N OF
DLH. LLWS LIKELY THIS MRNG W OF DLH DUE TO 25-30 KT WINDS ABV SFC
BASED TEMP INVSN.
&&
POINT TEMPS/POPS...
DLH 69 58 78 54 / 10 20 10 10
INL 76 55 78 48 / 20 20 10 10
BRD 78 57 81 54 / 10 10 10 10
HYR 74 58 80 55 / 10 10 10 10
ASX 73 57 81 55 / 10 10 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
$$
DONOFRIO/04
000
FXUS63 KMPX 180841
AFDMPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
341 AM CDT THU SEP 18 2008
.DISCUSSION...
HIGH PRESSURE CURRENTLY OVER THE UPPER GREAT LAKES WILL BE MOVING
EAST TODAY. PRESSURE GRADIENT ACROSS THE FA WILL TIGHTEN WITH
BREEZY SOUTH WINDS DEVELOPING. LOW LEVEL MOISTURE TRANSPORT AND
WAA MAXIMIZED TO OUR NORTH TODAY WITH BKN-OVC AC ALREADY COVERING
MUCH OF NORTHERN MN/WI...WITH SOME CLOUDINESS INTO RICE LAKE AND
LADYSMITH. 4KM NSSL WRF SHOWING SHOWERS AND THUNDERSTORMS
DEVELOPING LATE THIS MORNING OVER NW MN AND SPREADING EAST-
NORTHEAST DURING THE AFTERNOON. SOME VERY WEAK ECHOES ALSO NOTED
OVER EASTERN IA AND SE MN. THIS GOES ALONG WITH THE NAM/GFS
MOISTENING THE LOW LEVELS...SOME ISENTROPIC UPGLIDE ON THE 305K
THETA SURFACE AND A SHORT WAVE MOVING BY IN THE AFTERNOON.
MOISTURE IS BASICALLY CONFINED BETWEEN 800-900MB. LITTLE Q-VECTOR
FORCING FOUND ALOFT. KEPT THE FORECAST DRY BUT DID INCREASE CLOUD
COVER A LITTLE OVER THE EASTERN HALF OF THE CWA. PRESSURE GRADIENT
REMAINS OVER THE FA TONIGHT WITH A STEADY SOUTH WIND AND MILD
TEMPERATURES.
FRIDAY LOOKING RATHER WARM WITH AN 850MB THERMAL RIDGE RUNNING
WEST TO EAST ACROSS THE FA DURING THE AFTERNOON AHEAD OF AN
APPROACHING COLD FRONT. 850MB TEMPS PROGGED TO REACH 16 TO 19 DEG
C FROM KEAU TO KCNB. RAISED FORECAST HIGH TEMPS A FEW DEGREES. A
CANADIAN COLD FRONT WILL THEN SLIP SOUTH INTO THE FA FRIDAY NIGHT
AND BECOME STATIONARY OVER SOUTHERN MN AND ADJOINING AREAS OF WI
ON SATURDAY. A PRETTY MILD DAY STILL EXPECTED WITH THE LOW LEVEL
THERMAL RIBBON OVER SOUTHERN AREAS OF THE FA. SREF PRECIP
PROBABILITIES ESSENTIALLY NIL WITH DEEP LAYER MOISTURE AND FORCING
MINIMAL. KEPT SOME SMALL POPS NEAR THE KARX CWA FOR CONTINUITY.
SUNDAY THE PROCESS BEGINS ALL OVER AGAIN WITH THE BOUNDARY LIFTING
NORTH AND SOUTHERLY WINDS DEVELOPING AS ANOTHER SURFACE HIGH MOVES
EAST FROM THE UPPER GREAT LAKES. HOWEVER...THE CHANCES FOR RAIN WILL
BE ON THE INCREASE NEXT WEEK. THE 00Z GFS/ECMWF IN BETTER
AGREEMENT TONIGHT WITH THE GFS NOT AS DEEP ALOFT OVER THE PAST FEW
NIGHTS AS WELL AS BEING A LITTLE FASTER WITH THE TROF MOVING
ACROSS THE NORTHERN ROCKIES EARLY NEXT WEEK. A LEAD SHORT WAVE ON
BOTH SOLUTIONS DAMPENS OUT ON MONDAY OVER US WITH THE WESTERN CWA
HAVING SOME CHANCE FOR RAIN. CHANCES FOR RAIN INCREASING TUESDAY
AND WEDNESDAY AS THE TROF APPROACHES AND DEEPER MOISTURE INVADES
THE REGION.
&&
.AVIATION... /06Z TAF ISSUANCE/
MAINLY VFR AT ALL SITES THRU PRD AS HI PRES MVS EAST AND SELY FLOW
INCRSS. HOWEVER SM THREAT FOG LT AT EAU WITH SML T/TD SPRD AND CLR
SKIES UNDER HI PRES RIDGE. 850MB WNDS INCRS TO 30 KTS W MN BY 18Z
AND ACRS AREA BY 00Z SO XPCT WND GUSTS 20 TO 25 KTS TO DVLP...ESP
AXN/STC/RWF.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
RAH/BAP
| 
