High Wind in Kansas, June 8, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
641 PM CDT WED JUN 8 2011

...UPDATE TO AVIATION...

.SHORT TERM (TONIGHT THROUGH THURSDAY)...

SURFACE LOW SHOWING UP OVER THE NORTHEAST TX PANHANDLE AT MID
AFTERNOON WITH AN INVERTED TROUGH AND ASSOCIATED BOUNDARY
EXTENDING NORTHEASTWARD THROUGH THE SALINA AREA AND INTO FAR
NORTHWEST MO. CU HAVE BEEN DEVELOPING NEAR AND JUST NORTH OF
BOUNDARY IN A RELATIVELY UNFOCUSED AREA OF SURFACE CONVERGENCE.
CU HAS NOT BEEN DEVELOPING MUCH VERTICAL EXTENT TO THIS POINT.
HOWEVER...CONTINUED CONVERGENCE WITH SOME HEATING SHOULD LEAD TO
AT LEAST ISOLATED THUNDERSTORM DEVELOPMENT NEAR BOUNDARY BY
EARLY EVENING...WITH THE BEST IN THE FAR NORTHEAST WHERE CINH IS
WEAKENING THE MOST. MLCAPE OF 2000 TO 3000 J/KG AND RELATIVELY
WEAK DEEP LAYER SHEAR WOULD LEAD TO MAIN CONVECTIVE CONCERNS WITH
WIND AND HAIL.

HOW THIS CONVECTION EVOLVES LATER THIS EVENING AND OVERNIGHT IS
SOMEWHAT UNCERTAIN. IT WOULD APPEAR WITH BOUNDARY LAYER WINDS
INCREASING THIS EVENING...BEST CHANCE OF THUNDERSTORM ACTIVITY
AFTER MIDNIGHT WOULD BE SLIGHTLY ELEVATED TO NORTH OF BOUNDARY
OVER FAR NORTHERN/NORTHEASTERN KS AND SOUTHEAST NEB. BEST
CONVECTIVE CHANCES ARE CONFINED TO THE FAR NORTHEAST THURSDAY
MORNING. REDEVELOPMENT OF THUNDERSTORMS LIKELY SOMEWHERE IN NC/NE
KS LATER DURING THE AFTERNOON THURSDAY...BUT LOCATION OF BEST
CHANCES DIFFICULT TO PIN DOWN AT THIS TIME. WIND FIELDS AND SHEAR
WILL BE STRONGER ON THURSDAY SO THREAT FOR ORGANIZED SEVERE
WEATHER COULD BE BETTER.

THERE IS THE POTENTIAL FOR HEAVY RAINFALL TONIGHT WITH SLOW STORM
MOVEMENT..ESPECIALLY ACROSS FAR NORTH...BUT DO NOT EXPECT
COVERAGE OF THUNDERSTORMS TO WARRANT A FLASH FLOOD WATCH AT THIS
TIME.

GDP

&&
.LONG TERM (FRIDAY THROUGH WEDNESDAY)...

HIGHLIGHTS OF THE EXTENDED FORECAST INCLUDE 1) CHANCES FOR RAIN
WHICH COULD LEAD TO RISES IN AREA RIVERS AND STREAMS AND 2)
COOLER WEATHER COMPARED TO RECENT TEMPERATURES.

AN UPPER TROUGH WILL SWING THROUGH THE NORTHERN PLAINS INTO THE
MIDWEST ON FRIDAY. AN ASSOCIATED COLD FRONT WILL LINGER IN EAST
CENTRAL KANSAS FRIDAY AND WILL PROVIDE A FOCUS FOR THE POTENTIAL
OF ADDITIONAL THUNDERSTORM DEVELOPMENT. COOLER AIR BEHIND THE
FRONT ALONG WITH CLOUD COVER WILL KEEP HIGHS IN THE 80S.

SURFACE HIGH PRESSURE IS EXPECTED TO BUILD SOUTH FROM THE
NORTHERN PLAINS INTO THE CENTRAL PLAINS FRIDAY NIGHT AND
SATURDAY. A COOLER AND DRIER AIRMASS WILL ADVECT INTO NORTHEAST
KANSAS WITH MOST AREAS EXPERIENCING HIGHS IN THE LOW 80S. HAVE
MAINTAINED SLIGHT AND CHANCE POPS SOUTH OF INTERSTATE 70 WHERE
REMNANT BOUNDARY AND DAYTIME HEATING COULD PRODUCE SCATTERED
CONVECTION. IF THE SURFACE HIGH BUILDS FURTHER SOUTH AND/OR
PREVIOUS CONVECTION PRODUCES STRONG ENOUGH OUTFLOW THIS BOUNDARY
COULD END UP SOUTH OF THE FORECAST AREA WHICH WOULD WARRANT LOWER
POPS THAN CURRENTLY FORECAST.

FORECAST CONFIDENCE IS GREATER IN REGARDS TO POPS DURING THE
SATURDAY NIGHT AND SUNDAY TIME FRAME. IN RESPONSE TO HEIGHT FALLS
ALOFT...THE PRESSURE GRADIENT WILL TIGHTEN ACROSS THE PLAINS WITH
THE APPROACH OF AN UPPER TROUGH IN THE WESTERN UNITED STATES.
SOUTH WINDS WILL INCREASE LIFTING THE PREVIOUSLY MENTIONED
BOUNDARY NORTH AS A WARM FRONT INTO NORTHEAST KANSAS. MOISTURE
TRANSPORT AIDED BY A 50 KNOT LOW LEVEL JET WILL INTERACT WITH
THIS FRONT WITH NUMEROUS SHOWERS AND THUNDERSTORMS EXPECTED
ACROSS THE FORECAST AREA. INSTABILITY ALONG WITH THERMAL PROFILES
WOULD SUPPORT HEAVY RAIN...ALONG WITH A POTENTIAL OF MARGINALLY
SEVERE HAIL AND WIND. RUNOFF FROM HIGH RAINFALL
RATES...WIDESPREAD RAIN AND ADEQUATE RAINFALL ARE LIKELY TO
PRODUCE ELEVATED RIVER AND STREAM LEVELS WHICH COULD LEAD TO
FLOODING.

PRECIPITATION IS EXPECTED TO END FROM WEST TO EAST MONDAY WITH
THE LOW LEVEL JET AND MOISTURE TRANSPORT VEERING INTO WESTERN
MISSOURI. UPPER LEVEL RIDGING IS PROGGED TO BRIEFLY BUILD INTO
THE PLAINS BRINGING A BRIEF RETURN TO WARMER AND DRY WEATHER.

THE EXTENDED FORECAST MODELS BRING ANOTHER TROUGH THROUGH THE
NORTHERN PLAINS WITH A FRONT APPROACHING NORTHEAST KANSAS EARLY
NEXT WEEK WHICH WOULD SUPPORT ADDITIONAL CHANCES FOR
PRECIPITATION.

ANGLE

&&

.AVIATION...

COLD FRONT APPEARS TO HAVE STALLED NEAR MHK...WITH SLOWLY
INCREASING CUMULUS FIELD NEARBY. SOME QUESTION REMAINS ON HOW MUCH
IF ANY ACTIVITY WILL FORM ALONG THE FRONT GIVEN THE WEAK
FORCING...BUT WILL MAINTAIN VCTS AT MHK AND CB AT TOP AND FOE AND
CLOSELY WATCH TRENDS. SOME SIGNAL IN MVFR CLOUD DECK PERSISTS IN
RECENT RUNTS...BUT TOO LITTLE CONFIDENCE FOR ANY CEILING
INCLUSION. BOUNDARY SHOULD MIX NORTH THURSDAY AFTERNOON BUT A
MINOR STORM CONCERN EXISTS.

65

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE TOPEKA KS
354 PM CDT WED JUN 8 2011

KSZ008>012-020>024-026-034>040-054>056-058-059-092100-
REPUBLIC-WASHINGTON-MARSHALL-NEMAHA-BROWN-CLOUD-CLAY-RILEY-
POTTAWATOMIE-JACKSON-JEFFERSON-OTTAWA-DICKINSON-GEARY-MORRIS-
WABAUNSEE-SHAWNEE-DOUGLAS-LYON-OSAGE-FRANKLIN-COFFEY-ANDERSON-
354 PM CDT WED JUN 8 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL...NORTH
CENTRAL AND NORTHEAST KANSAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SCATTERED THUNDERSTORMS WILL BE POSSIBLE TONIGHT...MAINLY ALONG
AND NORTH OF INTERSTATE 70. SOME OF THE STRONGER STORMS COULD
PRODUCE UP TO QUARTER SIZE HAIL AND STRONG DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

THERE IS A CHANCE FOR MORE THUNDERSTORMS ACROSS THE AREA THURSDAY
AND THURSDAY NIGHT. SOME OF THE THUNDERSTORMS COULD BECOME SEVERE
ACROSS NORTHEAST KANSAS.

ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE FRIDAY. THESE
THUNDERSTORMS ARE EXPECTED TO REMAIN BELOW SEVERE THRESHOLDS.

STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE LATE SATURDAY
NIGHT INTO SUNDAY. HEAVY RAIN WILL BE LIKELY BRINGING THE
POTENTIAL OF LOCALIZED FLOODING ALONG WITH RISES IN AREA RIVERS
AND CREEKS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING IN PORTIONS OF THE
NORTH CENTRAL AND NORTHEAST.