Hail and Damaging Winds in Missouri, July 15, 2009

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
637 AM CDT WED JUL 15 2009

.DISCUSSION...

WIDELY SCATTERED ELEVATED CONVECTION DEVELOPED AGAIN LATE IN THE
EVENING OVER SOUTHEAST KS INTO SOUTHWEST/CENTRAL MO WHERE LOW LEVEL
MOISTURE TRANSPORT COMBINED WITH WEAK ISENTROPIC UPGLIDE (BEST
DEPICTED AT THE 315K LAYER). SCATTERED CONVECTION IS ALSO
OCCURRING ALONG A COLD FRONT FROM IA TO THE TX PANHANDLE. WILL
MONITOR THE CONVECTION ONGOING OVER THE AREA AND MAKE EARLY POPS A
LAST SECOND CALL. BETTER CHANCE FOR MORE ORGANIZED CONVECTION IN
THE NEAR TERM SHOULD STAY OFF TO THE NORTH AND NORTHEAST WITH
CONVECTION NOW OVER WESTERN IL/NORTHEAST MO.

00Z KSGF SOUNDING WAS SHOWING A CAPPING INVERSION IN 900MB-850MB
LAYER AS AN ELEVATED MIXED LAYER ADVECTED INTO THE REGION. MAIN
FORECAST CONCERN WILL BE IF/WHEN CAPPING WILL BREAK AS THE COLD
FRONT TO OUR NORTHWEST DROPS SOUTH INTO THE AREA...REACHING CLOSE
TO THE MO/AR/OK BORDERS BY 00Z/EARLY WED EVENING. NEAR TERM MODELS
DIFFER QUITE A BIT ON SFC TEMPERATURES AND RESULTANT INSTABILITY
BY MID/LATE AFTERNOON WITH THE GFS. MODIFYING GFS BUFR SOUNDINGS
FOR SOUTH CENTRAL MO USING MOS SFC TEMPS/DEW POINT RESULTS IN
MLCAPES IN THE 2500 J/KG NEIGHBORHOOD WITH MLCIN STILL AROUND -55
J/KG. NOT SURE WEAK FORCING PROGGED BY ALL MODELS ALONG THE FRONT
WILL BE ABLE TO BREAK THE CAP. HOWEVER...INCREASING LIFT ALONG AND
NORTH OF THE FRONTAL BOUNDARY WITH AN INCREASING LOW LEVEL JET MAY
RESULT IN CLUSTERS OF CONVECTION DEVELOPING THIS EVENING AND
OVERNIGHT AND LINGERING INTO THU MORNING. VERTICAL SHEAR INCREASES
SLIGHTLY WITH AN APPROACHING SHORTWAVE AND A SLIGHT DIP IN THE MID
LEVEL WESTERLIES. ENOUGH SHEAR AND ELEVATED INSTABILITY WILL BE
PRESENT FOR STORM ORGANIZATION WITH A RISK FOR HAIL/DAMAGING
WINDS THROUGH THU MORNING.

WOULD EXPECT THE CONVECTION TO WANE THU MORNING...BUT IT MAY
RE-INTENSIFY OVER SE KS/SOUTHERN MO AS EITHER EXISTING CONVECTION
BECOMES MORE SFC BASED IF IT CAN SURVIVE INTO THE AFTERNOON.
WITH ADEQUATE VERTICAL SHEAR AND VEERED WIND PROFILES
THU...STORMS MAY BE QUITE ACTIVE THU/THU EVENING...BUT THIS IS
VERY CONDITIONAL BASED ON BOUNDARY LOCATION...AND THE AMOUNT OF
INSTABILITY THAT CAN DEVELOP. THE OVERALL FOCUS FOR CONVECTION
WOULD LIKELY BE MORE OVER THE SOUTHERN CWFA VERSUS CENTRAL MO.

THE UPPER PATTERN WILL GRADUALLY SHIFT...WITH A LARGE SCALE UPPER
RIDGE DEVELOPING OVER THE WESTERN CONUS...AND AN UNSEASONABLY COOL
AIR MASS/UPPER TROUGHING OVER THE GREAT LAKES/OH VLY. THIS IS
EXPECTED TO PUSH THE FRONT FAR ENOUGH SOUTH AND WEST TO LIMIT
THUNDERSTORMS CHANCES BEYOND FRI MORNING. COOLER/DRYER AIR SHOULD
REMAIN IN PLACE THROUGH THE UPCOMING WEEKEND. DSA

&&

.AVIATION...

LOW LEVEL WIND SHEAR WILL PERSIST EARLY THIS MORNING AT AREA
TERMINAL SITES. OTHERWISE SCATTERED SHOWERS AND THUNDERSTORMS
WILL BE FOCUSED MAINLY TO THE NORTH AND EAST OF SPRINGFIELD THIS
MORNING. MORE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS IS EXPECTED
LATER TODAY AS A FRONT PUSHES INTO SOUTHERN MISSOURI. THIS WILL
BRING A GRADUAL WIND SHIFT TO THE NORTHEAST BY THIS EVENING.
SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE TONIGHT WITH
AREAS OF MVFR CEILINGS AND VISIBILITIES IN THE SHOWERS.

FOSTER

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SPRINGFIELD MO
110 PM CDT WED JUL 15 2009

KSZ073-097-101-MOZ055>058-066>071-077>083-088>098-101>106-161815-
BOURBON-CRAWFORD-CHEROKEE-BENTON-MORGAN-MILLER-MARIES-VERNON-
ST. CLAIR-HICKORY-CAMDEN-PULASKI-PHELPS-BARTON-CEDAR-POLK-DALLAS-
LACLEDE-TEXAS-DENT-JASPER-DADE-GREENE-WEBSTER-WRIGHT-NEWTON-
LAWRENCE-CHRISTIAN-DOUGLAS-HOWELL-SHANNON-MCDONALD-BARRY-STONE-
TANEY-OZARK-OREGON-
110 PM CDT WED JUL 15 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF THE MISSOURI
OZARKS AND EXTREME SOUTHEAST KANSAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

A COLD FRONT WILL MOVE INTO SOUTHEAST KANSAS AND CENTRAL MISSOURI
THIS AFTERNOON AND INTO THE FAR SOUTHERN MISSOURI OZARKS THIS
EVENING. SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP AHEAD
OF THE FRONT THROUGH THE AFTERNOON. STRONG INSTABILITY AND
MODERATE VERTICAL WIND SHEAR WILL BRING THE POTENTIAL OF STRONG
TO SEVERE THUNDERSTORMS AFTER 3 PM THIS AFTERNOON WITH THE
POTENTIAL CONTINUING OVERNIGHT AS A LOW LEVEL JET INCREASES.
ISOLATED STORMS WILL BE CAPABLE OF LARGE HAIL UP TO THE SIZE OF
GOLF BALLS AND DAMAGING WIND GUSTS UP TO 70 MPH ALONG WITH HEAVY
RAINFALL AND LOCALIZED FLOODING.

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

THUNDERSTORMS WILL BE ONGOING ACROSS PORTIONS OF THE MISSOURI
OZARKS AND EXTREME SOUTHEAST KANSAS THURSDAY MORNING. SUFFICIENT
INSTABILITY AND SHEAR SHOULD BE AVAILABLE FOR STRONG TO ISOLATED
SEVERE STORMS TO AFFECT THE AREA AS A COLD FRONT PUSHES THROUGH
THE REGION. THE MAIN CONCERN WITH ANY STORM THAT BECOME SEVERE
WOULD BE HAIL TO THE SIZE OF QUARTERS...WINDS AROUND 60 MPH AND
HEAVY RAINFALL. LOCALIZED FLOODING WILL BE POSSIBLE IN POOR
DRAINAGE AREAS.

THUNDERSTORMS WILL ALSO BE POSSIBLE LATE IN THE DAY THURSDAY AND
EARLY FRIDAY MORNING.

NO ADDITIONAL THUNDERSTORMS ARE EXPECTED FOR THE SATURDAY THROUGH
TUESDAY PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE THROUGH TONIGHT.

&&

THIS PRODUCT IS NOW AVAILABLE IN GRAPHICAL FORMAT...ALONG WITH
OTHER WEATHER...HYDROLOGICAL AND CLIMATE INFORMATION...AT
HTTP://WWW.CRH.NOAA.GOV/SGF(ALL LOWERCASE)

HATCH