Hail and Damaging Winds in Kansas, August 8, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
319 PM CDT MON AUG 8 2011

.DISCUSSION...

DAYS 1-2...

UPPER AIR ANALYSIS AND WATER VAPOR LOOP THIS MORNING PLACED AN
UPPER LEVEL TROUGH OVER EASTERN WYOMING AT 12Z. THIS SYSTEM HAS
BEEN MOVING SOUTHEAST AND WHICH BASED ON 18Z MODEL VERIFICATION
BOTH THE NAM AND GFS HAS BEEN DOING A DECENT JOB WITH THE TRACK OF
THIS UPPER LEVEL SYSTEM. AT 700MB LEVEL +16C TEMPERATURES WERE STILL
OBSERVED OVER SOUTHEAST KANSAS AS A COLD FRONT UNDERCUTS THIS WARM
AIR AND AS OF 18Z WAS BEGINNING TO MOVE INTO NORTHERN OKLAHOMA.
ANOTHER, WEAKER SURFACE BOUNDARY WAS MOVING SOUTH ACROSS SOUTHERN
NEBRASKA. ALTHOUGH AT THIS TIME THIS BOUNDARY IS A LITTLE DIFFICULT
TO PICK OUT ON THE SURFACE ANALYSIS BOTH THE NAM AND GFS NOT ONLY
PICK UP ON THIS FEATURE BUT ALSO MOVE THIS SECONDARY BOUNDARY INTO
NORTHERN KANSAS BY LATE DAY. WITH THIS SURFACE BOUNDARY MOVING
NEAR/INTO OUR NORTHERN COUNTY WARNING AREA LATE IN THE DAY ALONG
WITH THE APPROACHING THE UPPER LEVEL TROUGH AND MID LEVEL
INSTABILITY AM CURRENTLY UNABLE TO COMPLETELY RULE OUT A FEW
THUNDERSTORMS DEVELOPING LATE TODAY/EARLY TONIGHT NEAR THE
INTERSTATE 70 CORRIDOR.

THIS SECONDARY FRONT ALONG WITH SOME COOLER 850MB TEMPERATURES
WILL CONTINUE TO FILTER INTO SOUTHWEST KANSAS OVERNIGHT AND THIS
WILL STRENGTHEN THE 850MB BAROCLINIC ZONE DURING THE DAY ON
TUESDAY NEAR THE COLORADO BORDER. AT THIS TIME BASED MODEL
SOUNDINGS AND 850MB TEMPERATURE TRENDS EAST OF THE DEVELOPING
BAROCLINIC ZONE HAVE DECIDED TO CONTINUE TO LEAN TOWARDS THE SLIGHTLY
WARMER 00Z WEDNESDAY 850MB MIX DOWN TEMPERATURES FOR HIGHS TUESDAY
AFTERNOON.

ON TUESDAY NIGHT THE UPSLOPE FLOW WILL CONTINUE WHICH WILL DRAW
MORE HUMID AIR BACK INTO AREA. THE 12Z NAM IS NOT AS QUICK ON THE
RETURN OF LOW LEVEL MOISTURE INTO WESTERN KANSAS WHEN COMPARED TO
THE GFS BUT THE NAM DOES BRING SOME LOW LEVEL MOISTURE BACK INTO
MUCH OF THE AREA BY EARLY WEDNESDAY MORNING. AT THIS TIME
CONFIDENCE IS NOT HIGH ON HOW QUICKLY THIS MOISTURE WILL RETURN
BUT BOTH MODELS ARE IN DECENT AGREEMENT WITH LOW CLOUDS RETURNING
TO MUCH OF THE AREA BY EARLY WEDNESDAY. NOT ONLY WILL MOISTURE BE
ON THE INCREASE TUESDAY NIGHT BUT WARM AIR ADVECTION/ISENTROPIC
LIFT WILL ALSO IMPROVE...ESPECIALLY IN THE NORTH AS THE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET BEGINS TO APPROACH THE AREA. CHANCE
FOR PRECIPITATION FOR MUCH OF THE AREA STILL LOOKS ON TRACK WITH
THE BETTER OPPORTUNITY FOR STORMS DEVELOPING IN OUR
NORTH/NORTHEAST AREAS. CLOUD COVER AND PRECIPITATION CHANCES ON
WEDNESDAY SHOULD KEEP TEMPERATURES ON THE COOL SIDE MID WEEK AND
BASED ON THE DEPTH OF THE LOW LEVEL MOISTURE HAVE DECIDED TO HANG
ON THE THE CLOUD COVER A LITTLE LONGER AND LEAN TOWARDS THE
MET/MAV FOR HIGHS....ESPECIALLY IN THE NORTH.

DAYS 3-7...

JUST A FEW TWEAKS AND ADJUSTMENTS WERE MADE TO THE EXTENDED FORECAST
BUT THE SAME STORY WITH NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES
AND THE THREAT FOR DIURNAL MESOSCALE CONVECTIVE COMPLEXES CONTINUES
THROUGHOUT MUCH OF THE PERIOD.

MY PERIOD BEGINS WEDNESDAY EVENING. HAVE RETAINED THE HIGHEST POPS
TO SOUTHEAST CWFA IN ASSOCIATION WITH LIFT FROM A FRONTAL BOUNDARY.
THIS FRONT IS EXPECTED TO STALL NEAR THE OKLAHOMA/KANSAS BORDER PER
12Z GUIDANCE. AT THE UPPER LEVELS, A 250 HPA JET STREAK SHOULD BE
OVER MISSOURI WHICH WILL EFFECTIVELY PUT KANSAS IN THE RIGHT
ENTRANCE REGION - I.E. LIFT THROUGHOUT THE COLUMN. THE 12Z ECMWF IS
WEAKER WITH THIS UPPER LEVEL FEATURE AND HAS THE UPPER LEVEL WAVE
FURTHER EAST. THIS MIGHT BE THE REASON WHY THE MODEL WANTS TO CLEAR
THE AREA OF QPF QUICKER THAN THE GFS. IN ORDER TO BLEND IN WITH OUR
NEIGHBORS, HAVE SIDED MORE WITH THE GFS AND THE PREVIOUS FORECAST.
BY THURSDAY, THE AFOREMENTIONED FRONTAL BOUNDARY WILL BEGIN TO MORE
NORTH AS A WARM FRONT. WE COULD SEE SOME AFTERNOON AND EVENING
CONVECTIVE DEVELOPMENT ALONG THIS BOUNDARY BUT I DON'T HAVE THE
GREATEST CONFIDENCE IN WHERE THE FRONT WILL BE. AS A RESULT, HAVE
BROAD BRUSHED THE AREA WITH SLIGHT POPS FOR THURSDAY. HIGH
TEMPERATURES WILL BE NEAR NORMAL WITH UPPER 80S TO THE NORTH AND MID
90S TO THE SOUTH. THE UPPER LEVEL JET LIFTS NORTH SO THERE WON'T BE
AS STRONG DYNAMICS AS THE PREVIOUS NIGHT AND HENCE THE 15 TO 20
PERCENT POPS. BY FRIDAY, AND UPPER LEVEL SHORTWAVE TROUGH MOVES
ACROSS THE NORTHERN PLAINS. THIS FEATURE WILL USHER IN ANOTHER COLD
FRONT AND WE WILL SEE A BETTER CHANCE FOR MORE WIDESPREAD CONVECTION
FRIDAY NIGHT INTO EARLY SATURDAY MORNING. TEMPERATURES WILL BE
WARMER AHEAD OF THE FRONT WITH COMPRESSIONAL WARMING. LOW 90S TO THE
NORTH. UPPER 90S TO THE SOUTH. THE REST OF THE FORECAST WAS BLENDING
FROM PREVIOUS AND CONSALL. WE COULD SEE SOME DIURNAL THUNDERSTORMS -
MCS'S AGAIN EACH DAY. TEMPERATURES WILL BE SEASONAL AND THEN WARM UP
TO ABOVE NORMAL LEVELS TOWARDS MID AUGUST AS 500 HPA HEIGHTS
INCREASE IN RESPONSE TO MORE RIDGING ALOFT. -SUGDEN

&&

.AVIATION...

FORECAST CONCERNS FOR THE TAFS ARE CONVECTIVE PROSPECTS TONIGHT AND
THEN POSSIBLE BR/FG TOMORROW MORNING. IN THE SHORTER TERM,
NORTHERLY TO NORTHEASTERLY FLOW SHOULD PREVAIL THIS AFTERNOON IN THE
WAKE OF A DEPARTING SURFACE LOW AND COLD FRONT. FOLLOWING HRRR,
COULD SEE SOME CUMULUS LATE THIS AFTERNOON AND INTO EARLY EVENING
PER UPDRAFT VELOCITY FIELDS. THE 12Z NAM HINTS AT CONVECTION MOVING
NEAR INTERSTATE 70 THIS EVENING WHICH COULD IMPACT KHYS. THE 12Z 4
KM WRF INDICATES AN MCS MOVING FROM NEBRASKA INTO KANSAS AS WELL.
THE GFS AND TO A LESSER (MORE ISOLATED) EXTENT THE HRRR SHOWS FAIRLY
DRY CONDITIONS WITH SUBSIDENCE PREVAILING IN THE WAKE OF THE
AFOREMENTIONED DEPARTING SYSTEM. HAVE INSERTED CB GROUPS IN FOR KHYS
BUT SUBSIDENCE SHOULD KEEP KGCK AND KDDC DRY THIS EVENING. NEXT
CONCERN IS THE POTENTIAL FOR FOG...BUFKIT SOUNDINGS ARE SUPPORTIVE
OF PATCHY FOG AND HAVE THE LOWEST CIGS TOMORROW MORNING FOR KHYS.
CONFIDENCE IS NOT REAL HIGH FURTHER SOUTH ALTHOUGH NAM BUFR/BUFKIT
SOUNDINGS DO SHOW THE POTENTIAL FOR BR AT KDDC TOMORROW MORNING. THE
HIGHEST CONFIDENCE FOR FOG IS ALONG INTERSTATE 70 WHERE THEY HAVE
SEEN MORE RAINFALL OVER THE LAST FEW DAYS AND THE GROUND IS
SUBSEQUENTLY WETTER WITH HIGHER MOISTURE FLUXES PRESENT. AS A RESULT
OF THE ABV, HAVE REDUCED CIGS TOMORROW MORNING WITH THE LOWEST CIGS
(POTENTIALLY IFR) AT KHYS. LATER SHIFTS CAN ADJUST IF FG TRENDS
SUPPORT OTHERWISE. -SUGDEN

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  65  94  65  86 /  10  10  60  50
GCK  64  94  63  85 /  10  10  50  40
EHA  64  94  67  91 /  10  10  20  20
LBL  65  95  66  92 /  10  10  30  30
HYS  64  90  63  81 /  20  10  70  60
P28  68  98  69  90 /  20  10  50  40

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

FN18/36/36

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE DODGE CITY KS
1038 AM CDT MON AUG 8 2011

KSZ030-031-043>046-061>066-074>081-084>090-091545-
TREGO-ELLIS-SCOTT-LANE-NESS-RUSH-HAMILTON-KEARNY-FINNEY-HODGEMAN-
PAWNEE-STAFFORD-STANTON-GRANT-HASKELL-GRAY-FORD-EDWARDS-KIOWA-
PRATT-MORTON-STEVENS-SEWARD-MEADE-CLARK-COMANCHE-BARBER-
1038 AM CDT MON AUG 8 2011 /938 AM MDT MON AUG 8 2011/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL...SOUTH
CENTRAL...SOUTHWEST AND WEST CENTRAL KANSAS.

.DAY ONE...TODAY AND TONIGHT

SCATTERED SEVERE THUNDERSTORMS ARE POSSIBLE MAINLY NORTHEAST OF
LINE FROM DIGHTON TO JETMORE AND PRATT LATE THIS AFTERNOON AND
EVENING. DAMAGING WINDS OVER 70 MPH AND LARGE HAIL TO GOLFBALL
SIZE ARE POSSIBLE.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS EASTERN COLORADO LATE
TUESDAY AFTERNOON AS MOIST SOUTHEASTERLY UPSLOPE FLOW DEVELOPS.
THESE STORMS WILL MOVE INTO FAR SOUTHWEST AND WEST-CENTRAL KANSAS
DURING THE MID TO LATE EVENING HOURS...WITH A FEW OF THE STORMS
POSSIBLY BEING SEVERE. A MORE ORGANIZED CLUSTER OF STRONG TO
SEVERE THUNDERSTORMS WILL DEVELOP DURING THE OVERNIGHT HOURS AS A
STRONG LOW LEVEL JET FORMS. THE GREATEST RISK FROM EVENING AND OVERNIGHT
THUNDERSTORMS LATE TUESDAY NIGHT WILL BE LARGE HAIL TO HALF-DOLLAR
SIZE AND DAMAGING WINDS TO 60 MPH.

ADDITIONAL THUNDERSTORMS ARE EXPECTED NEAR A SURFACE LOW ALONG THE
WESTERN KANSAS-OKLAHOMA BORDER WEDNESDAY. A FEW SEVERE STORMS WILL
BE POSSIBLE. ANOTHER COLD FRONT WILL MOVE INTO WESTERN KANSAS
FRIDAY PROVING YET ANOTHER CHANCE FOR STRONG TO SEVERE
THUNDERSTORMS DURING THE LATE AFTERNOON AND EVENING HOURS.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTERS MAY BE REQUIRED LATE THIS AFTERNOON AND EVENING
MAINLY NORTH AND EAST OF A DIGHTON TO JETMORE TO PRATT LINE.

&&

FOR MORE INFORMATION VISIT OUR WEBPAGE AT HTTP://WEATHER.GOV/DDC

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