[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 231955
SWODY1
SPC AC 231953

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0253 PM CDT SUN JUL 23 2006

VALID 232000Z - 241200Z

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND TONIGHT OVER
NRN MN...NRN WI AND THE WRN UP OF MI...

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER
PORTIONS OF THE SRN ATLANTIC COAST...

...NRN MN/NRN WI/WRN UP OF MI...

AFTERNOON WATER VAPOR IMAGERY SHOWS AMPLIFYING SHORT WAVE TROUGH
DIGGING SEWD INTO WRN ONTARIO WITH A WEAKER SRN IMPULSE OVER FAR
SERN MANITOBA. CONSIDERABLE CLOUDINESS HAS LIMITED DAYTIME HEATING
OVER MUCH OF THE ARROWHEAD...THOUGH AIR MASS FROM N OF HIB WWD HAS
WARMED INTO THE UPPER 80S/LOWER 90S.  THIS HEATING COUPLED WITH
RELATIVELY STEEP MID-LEVEL LAPSE RATES AND MODEST BOUNDARY LAYER
MOISTURE ARE CONTRIBUTING TO A MODERATELY UNSTABLE ENVIRONMENT W OF
THICKER CLOUD SHIELD WITH MLCAPES OF AROUND 1000 J/KG.

BASED ON SATELLITE TRENDS AND LATEST SHORT TERM MODEL GUIDANCE...IT
APPEARS THAT TSTMS WILL INCREASE IN COVERAGE LATE THIS AFTERNOON
INTO TONIGHT ALONG DIFFERENTIAL HEATING BOUNDARY AND COLD FRONT /NOW
PUSHING INTO NWRN MN/. CURRENT DLH VWP AND FORECAST SOUNDINGS
INDICATE PRONOUNCED LOW-LEVEL HODOGRAPH CURVATURE WITH 30-40 KTS OF
DEEP-LAYER SHEAR.  THUS...EXPECT THE POTENTIAL FOR ORGANIZED SEVERE
STORMS...INCLUDING SUPERCELLS CAPABLE OF DAMAGING WINDS AND LARGE
HAIL.  THIS THREAT MAY TEND TO DIMINISH BY LATE EVENING INTO
OVERNIGHT AS BOUNDARY LAYER SLOWLY STABILIZES. A FEW OF THE MORE
INTENSE ELEVATED STORMS WILL REMAIN CAPABLE OF SOME HAIL OVERNIGHT.

FOR ADDITIONAL SHORT TERM GUIDANCE...PLEASE SEE MCD 1614.

...SRN ATLANTIC COAST...

LINGERING CLOUDINESS HAS SLOWED DESTABILIZATION OF AIR MASS AHEAD OF
WEAKENING FRONT ACROSS THE PIEDMONT AND COASTAL PLAIN THROUGH EARLY
AFTERNOON.  MORE RECENTLY...CLOUDS HAVE THINNED...ALLOWING FOR
STRONGER DIABATIC HEATING WHICH HAS COMBINED WITH A MOIST BOUNDARY
LAYER TO INCREASE MLCAPES TO 1000-2000 J/KG.  AREA VWPS AND RUC
OBJECTIVE FIELDS INDICATE THAT MID-LEVEL WINDS ARE GRADUALLY
WEAKENING WITH THE SLOW NEWD MOVEMENT OF UPPER TROUGH. HOWEVER...AN
AXIS OF 30-35 KT WSWLY FLOW STILL EXISTS ACROSS NRN NC WHICH IS
ENHANCING SHEAR ACROSS NRN PORTIONS OF SLIGHT RISK AREA.

GIVEN THE MODERATE INSTABILITY...EXPECT THAT STORMS SHOULD CONTINUE
TO INCREASE IN COVERAGE AND INTENSITY THROUGH THE LATE AFTERNOON AND
EARLY EVENING HOURS WITH THE MAIN THREAT BEING LOCALLY DAMAGING
WINDS WITH ANY OF THE MORE INTENSE DOWNBURSTS.

FOR ADDITIONAL SHORT TERM GUIDANCE...PLEASE SEE MCD 1613.

..MEAD.. 07/23/2006