SPC AC 091625
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1125 AM CDT SUN JUL 09 2006
VALID 091630Z - 101200Z
...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING FOR ERN
WI AND LOWER MI....
...GREAT LAKES AREA THROUGH THIS EVENING...
A PRONOUNCED MID LEVEL TROUGH OVER NW WI/WRN UPPER MI/LAKE SUPERIOR
WILL CONTINUE SEWD OVER THE GREAT LAKES THROUGH EARLY MONDAY. A
WEAK SURFACE LOW OVER ERN UPPER MI WILL MOVE TOWARD SWRN ONTARIO IN
ADVANCE OF THE MID LEVEL TROUGH...WHILE A TRAILING COLD FRONT
PROGRESSES SEWD ACROSS MI/WI/IA. THE PRE-FRONTAL WARM SECTOR IS
CHARACTERIZED BY BOUNDARY LAYER DEWPOINTS IN THE MID 60S...AND
SURFACE HEATING WILL CONTRIBUTE TO MLCAPE VALUES APPROACHING 1500
J/KG THIS AFTERNOON.
EXPECT SCATTERED THUNDERSTORMS TO FORM IN CONJUNCTION WITH DEEP
LAYER ASCENT ALONG THE COLD FRONT THIS AFTERNOON ACROSS NRN LOWER MI
AND POSSIBLY ERN WI. THE MODERATE INSTABILITY AND NWLY LOW-MID
LEVEL SHEAR OF 30-40 KT SHOULD SUPPORT A BROKEN BAND OF
STORMS...SOME OF WHICH COULD DEVELOP SUPERCELL STRUCTURES. THE
PRIMARY SEVERE THREATS WILL BE WIDELY SCATTERED DAMAGING GUSTS AND
ISOLATED LARGE HAIL FROM MID AFTERNOON INTO THIS EVENING.
...NRN VA/CENTRAL AND ERN PA/S CENTRAL NY AREA THIS AFTERNOON...
WATER VAPOR IMAGERY AND UPPER AIR ANALYSES SHOW A MID LEVEL LOW AND
ASSOCIATED COLD POOL MOVING NWD FROM VA TOWARD ERN PA. VISIBLE
IMAGERY SHOWS SEVERAL AREAS OF GROWING CUMULUS FROM NRN VA ACROSS
ERN PA TO S CENTRAL NY BENEATH THE MID LEVEL COLD POOL...WITH
ADDITIONAL DESTABILIZATION AND THUNDERSTORM DEVELOPMENT LIKELY THE
NEXT FEW HOURS. OBSERVED AND FORECAST SOUNDINGS SHOW THE POTENTIAL
FOR HAIL APPROACHING SEVERE LIMITS THIS AFTERNOON AS A RESULT OF
MODEST LOW-MID LEVEL LAPSE RATES AND COOL MID LEVEL TEMPERATURES
/-15 C AT 500 MB/.
..THOMPSON/GUYER.. 07/09/2006
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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