Issued by NWS Springfield, MO
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23 24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
000
FXUS63 KSGF 052122
AFDSGF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
322 PM CST WED NOV 5 2008
.DISCUSSION...
MAIN FORECAST FOCUS WILL BE THE THREAT FOR SEVERE THUNDERSTORMS OVER
THE NEXT 12 TO 18 HOURS AS A STRONG STORM SYSTEM CROSSES THE
CENTRAL UNITED STATES. MUCH COOLER WEATHER IS THEN EXPECTED FROM THE
UPCOMING WEEKEND INTO NEXT WEEK. ANOTHER STORM SYSTEM IS EXPECTED
TO IMPACT THE AREA SOMETIME IN THE MONDAY TO WEDNESDAY TIME FRAME.
TONIGHT...STRONG UPPER LEVEL LOW PRESSURE WILL SLOWLY PUSH EAST
ACROSS THE CORN BELT. AT THE SURFACE...A COLD FRONT WILL PUSH INTO
SOUTHEAST KANSAS AND WESTERN MISSOURI LATE TONIGHT...MAKING IT TO
THE HIGHWAY 65 CORRIDOR BY SUNRISE. STRONG TO SEVERE STORMS ARE
EXPECTED ALONG THIS FRONT...AS WELL AS ALONG A PRE FRONTAL TROUGH
THIS EVENING AND OVERNIGHT. PLEASE REFER TO THE MESOSCALE
CONVECTIVE DISCUSSION BELOW FOR GREATER DETAIL ON THE SEVERE
WEATHER THREAT. BRISK SOUTH TO SOUTHEAST WINDS AHEAD OF THE FRONT
WILL SHIFT TO THE WEST. SPEAKING OF WINDS...WE HAVE NOT MET WIND
ADVISORY CRITERIA UP TO THIS POINT. WILL LIKELY BE CANCELLING THE
WIND ADVISORY BY 4 PM.
THURSDAY...THAT FRONT WILL QUICKLY PUSH EAST OUT OF CENTRAL AND
SOUTH CENTRAL MISSOURI IN THE MORNING. THE THREAT FOR
THUNDERSTORMS WILL END ONCE THE FRONT EXITS THE AREA. WE MAY
ACTUALLY SEE A BRIEF PERIOD OF CLEARING AS A DRY SLOT WORKS INTO
THE AREA. WRAP AROUND MOISTURE MAY THEN BRING MORE CLOUDINESS INTO
THE AREA BY THE AFTERNOON...ESPECIALLY OVER CENTRAL MISSOURI.
TEMPERATURES ARE A TOUGH CALL GIVEN THE INCREASING CLOUD COVER AND
COOLING LOW LEVELS. GENERALLY SPLIT THE DIFFERENCE BETWEEN THE MAV
AND MET. THURSDAY WILL AGAIN BE WINDY AS LOW LEVEL PRESSURE
GRADIENTS REMAIN RATHER TIGHT. WINDS WILL ALSO BECOME GUSTY BY THE
AFTERNOON AS THE LOW LEVELS OF THE ATMOSPHERE EFFICIENTLY MIX OUT.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...THAT UPPER LEVEL LOW
PRESSURE WILL FINALLY BEGIN TO PUSH EAST INTO THE GREAT LAKES. ONE
MORE UPPER LEVEL WAVE WILL COME AROUND THE SOUTHERN FLANK OF THE
LOW AND DRIVE A WEAK SURFACE TROUGH ACROSS THE AREA. NOT OUT OF
THE QUESTION WE COULD SEE A LIGHT SHOWER OR TWO UP ACROSS CENTRAL
MISSOURI ON FRIDAY. TEMPERATURES WILL BE ON THE COOL SIDE AS 850
MB TEMPERATURES HOVER AT OR BELOW ZERO DEGREES CELSIUS.
UPCOMING WEEKEND...THE AREA WILL REMAIN UNDER A CYCLONIC NORTHWEST
FLOW ALOFT. MOISTURE LOOKS PRETTY LIMITED SO AM NOT EXPECTING ANY
PRECIPITATION. THE COOL TEMPERATURES WILL CONTINUE WITH HIGHS
STRUGGLING TO GET INTO THE UPPER 40S AND LOWER 50S OVER MOST AREAS.
EARLY NEXT WEEK...LONG WAVE CHARTS CONTINUE TO FAVOR DIGGING OF
ENERGY OUT OF THE PACIFIC NORTHWEST. MEDIUM RANGE MODELS CONTINUE
TO INDICATE ENERGY DIVING INTO THE FOUR CORNERS REGION AND
EVENTUALLY EJECTING OUT TOWARDS THE OZARKS. STILL NOT A REAL GOOD
SIGNAL FOR TIMING...BUT FEEL THAT SLIGHT TO LOW END CHANCE POPS
ARE WARRANTED STARTING SUNDAY NIGHT AND MONDAY. DO NOT SEE ANY BIG
WARM UPS AS LOW LEVEL TRAJECTORIES WILL LIKELY REMAIN OUT OF THE
EAST AND NORTHEAST.
SCHAUMANN
&&
.AVIATION...
FOR THE 18Z KSGF/KJLN TAFS...THERE WILL BE SEVERAL AVIATION
HAZARDS THAT ARE EXPECTED TO AFFECT THE TAF SITES THROUGH THE NEXT
24 HOURS.
GUSTY SOUTHERLY WINDS WILL CONTINUE TO AFFECT THE TAF
SITES THIS AFTERNOON INTO THE OVERNIGHT HOURS...AHEAD OF AN
APPROACHING COLD FRONT. AS THE FRONT MOVES INTO WESTERN
KANSAS...SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF
THE FRONT. THE BEST CHANCES FOR THESE STORMS WILL OCCUR ACROSS
SOUTHEASTERN KANSAS AND NORTHWESTERN MISSOURI...HOWEVER A FEW OF
THESE STORMS MAY MOVE INTO EXTREME SOUTHWESTERN MISSOURI THIS
EVENING. HAVE INCLUDED CB IN THE KJLN TAF TO ACCOUNT FOR THIS...AS
CONFIDENCE IS TOO LOW TO INCLUDE A TEMPO OR PREVAIL GROUP AT THIS
TIME. THESE STORMS WILL HAVE THE POTENTIAL OF BECOMING STRONG TO
SEVERE.
AS THE FRONT PUSHES EAST A SQUALL LINE IS LIKELY TO DEVELOP NEAR
THE FRONT AND WILL PUSH THROUGH THE TAF SITES OVERNIGHT...FIRST AT
THE KJLN SITE THEN THE KSGF SITE. HEAVY RAINFALL AND GUSTY WINDS
WILL BE POSSIBLE WITH THESE STORMS. HAVE INCLUDED A TEMPO GROUP
FOR THIS ACTIVITY AS CONFIDENCE IS HIGHER IN THIS OCCURRING.
A STRONG LOW LEVEL JET WILL REMAIN ACROSS THE AREA INTO THE
OVERNIGHT HOURS...AND HAVE KEPT THE LOW LEVEL WIND SHEAR IN THE
TAFS TO ACCOUNT FOR THE WIND SHEAR.
WISE
&&
.PREV DISCUSSION...
/ISSUED 130 PM CST WED NOV 5 2008/
...MESOSCALE CONVECTIVE DISCUSSION...
CONDITIONS COMING TOGETHER TO SUPPORT RAPID THUNDERSTORM
DEVELOPMENT DURING THE MID/LATE AFTERNOON HOURS.
AT 100 PM...SFC ANALYSIS INDICATES A STRONG AREA OF LOW PRESSURE
OVER SOUTHEASTERN SOUTH DAKOTA. A COLD FRONT EXTENDS SOUTHWARD
FROM THIS LOW THROUGH EASTERN NEB...CENTRAL KS AND INTO THE
PANHANDLES OF OK AND TX. A DRYLINE IS LOCATED ROUGHLY FROM
CENTRAL KS SOUTHWARD INTO WESTERN OK. A BROAD AREA OF PRESSURE
FALLS IS LOCATED AHEAD OF THE SFC FRONTS. THE TIGHTENING PRESSURE
GRADIENT HAS KEPT WINDS QUITE GUSTY...WITH SUSTAINED WINDS AROUND
25 MPH OR SO AND GUSTS NEAR 40 MPH.
STRONG LOW LEVEL WINDS...AROUND 40KT AT 925MB AND 40KT TO 50KT
AT 850MB...HAVE AIDED IN CONTINUED MOISTURE ADVECTION AHEAD OF
THE DRYLINE AND COLD FRONT. SFC DEWPOINTS ARE IN THE UPPER 50S TO
AROUND 60F...AND LITTLE CHANGE IN VALUES ARE EXPECTED AHEAD OF THE
FRONT. OVER THE OZARKS...THERE HAS BEEN A DECENT MOISTURE GRADIENT
FROM WEST TO EAST. UPPER 50S DEWPOINTS ARE MAKING THEIR WAY INTO
AREAS NEAR THE MO/KS STATE LINE...BUT VALUES ARE STILL ONLY AROUND
50F OVER THE EASTERN OZARKS. STRONG FLOW JUST OFF THE SFC AND A
MORE SOUTHERLY OR JUST SOUTH OF WEST COMPONENT TO THE SFC WILL
WILL RESULT IN A SLOW...BUT STEADY INCREASE IN DEWPOINT ACROSS THE
REST OF THE AREA THIS AFTERNOON.
ALOFT...THERE ARE A FEW FEATURES OF INTEREST TO NOTE. FIRST...A
100KT JET STREAK LOCATED ON THE EASTERN PERIPHERY OF THE DEEP
TROUGH OVER THE ROCKIES HAS RESULTED IN BROAD SCALE LIFT. THIS IS
HIGHLIGHTED IN WAT VAP IMAGERY BY A PLUME OF MOISTURE FROM THE TX
PANHANDLE THROUGH WESTERN AND CENTRAL PORTIONS OF OK/KS. ANOTHER
120KT JET STREAK IS GEARING UP ON THE WESTERN PERIPHERY OF THE
TROUGH AND THERE ARE INCREASING INDICATIONS OF LIFT OVER NEW
MEXICO IN THE WAT VAP IMAGERY. LOOKING AT 18Z RAOBS AT KTOP AND
KOUN...IT IS CLEAR THAT THE BROAD SCALE LIFT AHEAD OF THE TROUGH
HAS BEEN ENOUGH TO SUBSTANTIALLY WEAKEN A RATHER STAUNCH CAP THAT
WAS OBSERVED WITH THE 12Z RAOBS.
OVER THE NEXT FEW HOURS...THROUGH APPROXIMATELY 430 PM...
CONDITIONS WILL REMAIN QUIET OVER EXTREME SE KS AND THE MO
OZARKS...SANS A FEW WAA SHRA OVER WESTERN ZONES. ALL EYES WILL BE
FOCUSED ON A DEVELOPING PREFRONTAL TROUGH OVER SE KS AND NE OK AS
BROAD SCALE LIFT FINALLY ZAPS THE REMAINING CAP AND DISCRETE
SUPERCELLS ERUPT. AFTER 430 PM...STORMS THAT HAVE DEVELOPED OVER
SE KS AND NE OK WILL QUICKLY SPREAD TO THE NORTHEAST AND IMPINGE
ON OUR EXTREME SE KS AND FAR WESTERN MO COUNTIES.
TO SAY THE LEAST...THERE IS SUBSTANTIAL DEEP LAYER AND LOW LEVEL
SHEAR. WITH DEWPOINTS SETTLING FIRMLY IN THE UPPER 50S TO AROUND
60F...MLCAPE AROUND 1000 J/KG IS EXPECTED. LARGE HAIL...DAMAGING
WIND GUSTS AND A FEW TORNADOES ARE EXPECTED. GIVEN SUCH
SUBSTANTIAL LOW LEVEL SHEAR...ANY STORMS NEAR THE HIGHEST AXIS OF
INSTABILITY WILL RUN AN INCREASED RISK FOR A FEW STRONG...LONG
LIVED TORNADOES.
DURING THE EVENING HOURS...SUPERCELLS WILL CONGEAL INTO A SQUALL
LINE AS THE COLD FRONT ACCELERATES TO THE EAST. THIS WILL
TRANSITION THE SEVERE WEATHER RISK TO DAMAGING STRAIGHT LINE WINDS
AND A FEW EMBEDDED TORNADOES FOR AREAS ALONG AND WEST OF THE
HIGHWAY 65 CORRIDOR. AS THIS LINE HEADS FURTHER INTO THE OZARKS
OVERNIGHT...A GENERAL WEAKENING TREND IS EXPECTED...THOUGH THE
RISK FOR DAMAGING WIND GUSTS WILL REMAIN.
GAGAN
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...WIND ADVISORY UNTIL 6 PM CST THIS AFTERNOON FOR MOZ066-067-077-
078-088-089-093-094-101-102.
KS...WIND ADVISORY UNTIL 6 PM CST THIS AFTERNOON FOR KSZ073-097-101.
&&
$$
