[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 251725
SWODY2
SPC AC 251724

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1224 PM CDT FRI AUG 25 2006

VALID 261200Z - 271200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF THE GREAT
LAKES AND NRN OH VALLEY SEWD TO THE DELMARVA...

...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF THE CNTRL/SRN
HIGH PLAINS EWD TO THE OZARK PLATEAU...

...SYNOPSIS...

ACTIVE WAVE TRAIN WITHIN PRIMARY BELT OF POLAR WESTERLIES WILL EXIST
ACROSS CANADA DURING THE DAY TWO PERIOD WITH A LOWER LATITUDE UPPER
LOW EVOLVING INTO AN OPEN WAVE OVER THE GREAT BASIN INTO CNTRL
ROCKIES.  IN THE LOW-LEVELS...SURFACE LOW ASSOCIATED WITH A WEAK
IMPULSE MOVING THROUGH THE GREAT LAKES WILL DEVELOP EWD FROM LAKE MI
INTO SWRN ONTARIO WHILE TRAILING COLD FRONT SLOWLY SAGS SWD THROUGH
THE MID MS VALLEY AND SRN HIGH PLAINS. TO THE E...QUASI-STATIONARY
BOUNDARY...DELINEATING WRN EDGE OF ANTICYCLONE OVER ME INTO NEW
BRUNSWICK...WILL EXTEND FROM THE GREAT LAKES LOW SEWD TO THE MID
ATLANTIC COAST.

...GREAT LAKES/NRN OH VALLEY TO THE DELMARVA...

SHORT WAVE TROUGH CURRENTLY OVER CNTRL WY IS FORECAST TO TRANSLATE
NEWD THROUGH THE NRN PLAINS AND UPPER MS VALLEY DURING THE DAY ONE
PERIOD...AND EVENTUALLY MORE EWD THROUGH LOWER MI INTO NY
SATURDAY/SATURDAY NIGHT.  FORCING FOR ASCENT ASSOCIATED WITH THIS
FEATURE AND CONVERGENCE ALONG ABOVE MENTIONED LOW-LEVEL BOUNDARIES
WILL PROVIDE THE FOCUS FOR STRONG TO SEVERE STORMS DURING THE
AFTERNOON AND EVENING HOURS.

IT APPEARS THAT CLOUDS/ONGOING PRECIPITATION MAY SLOW
DESTABILIZATION PROCESS NEAR SURFACE FRONTAL SYSTEM SATURDAY. 
HOWEVER...COMPARABLY STRONGER DIABATIC HEATING AND MOIST BOUNDARY
LAYER CONDITIONS WITHIN INFLOW AIR MASS FROM CNTRL MO/IL INTO NRN
IND/SRN LOWER MI...AND FARTHER E OVER WV/MD/NRN VA WILL CONTRIBUTE
TO MODERATE AFTERNOON INSTABILITY WITH MLCAPES OF 1000-2000 J/KG. 
AS THIS OCCURS...EXPECT A GRADUAL INCREASE IN STORM COVERAGE AND
INTENSITY THROUGH THE AFTERNOON FROM VICINITY OF SURFACE LOW OVER
CNTRL LOWER MI SWWD ALONG FRONT INTO NRN PARTS OF IND/IL...AND SEWD
ALONG QUASI-STATIONARY BOUNDARY FROM WRN NY INTO PA/MD/NJ.

STRONGEST VERTICAL SHEAR OWING TO ENHANCED LOW-LEVEL WAA/VEERING
WIND PROFILES WILL EXIST FROM LOWER MI SURFACE LOW SEWD ALONG
QUASI-STATIONARY BOUNDARY WHERE POTENTIAL WILL EXIST FOR
ORGANIZED...ROTATING UPDRAFTS CAPABLE OF DAMAGING WINDS...SOME
SEVERE HAIL AND PERHAPS A TORNADO OR TWO.  ALONG COLD
FRONT...VERTICAL SHEAR PROFILES ARE MUCH MORE
UNIDIRECTIONAL...THOUGH 30-35 KTS OF VERTICAL SPEED SHEAR WILL BE
SUPPORTIVE OF ORGANIZED STORMS CAPABLE OF SEVERE WINDS AND HAIL.

...CNTRL/SRN HIGH PLAINS INTO OZARK PLATEAU...

RICHEST BOUNDARY LAYER MOISTURE AND RESULTANT DESTABILIZATION
/MLCAPES OF 1500-3000 J/KG/ IS EXPECTED TO OCCUR ALONG W-E PORTION 
OF SYNOPTIC FRONT FROM OK/TX PNHDLS ENEWD INTO CNTRL/SRN MO. DESPITE
THE ABSENCE OF ANY APPRECIABLE LARGE-SCALE FORCING FOR
ASCENT...STRONG DIABATIC HEATING WITHIN PRE-FRONTAL AIR MASS WILL
CONTRIBUTE TO AN INCREASE IN TSTM ACTIVITY THROUGH THE AFTERNOON AND
EVENING HOURS ALONG LENGTH OF FRONTAL ZONE.  DEEP LAYER BULK SHEAR
WILL REMAIN MARGINAL /25-30 KTS/ FOR ORGANIZED SEVERE
STORMS...THOUGH THE MODERATE INSTABILITY AND PRESENCE OF STEEP LOW
LEVEL LAPSE RATES INDICATE THE POTENTIAL FOR DAMAGING WIND GUSTS AND
PERHAPS SOME SEVERE HAIL.

OVER THE HIGH PLAINS REGION FROM SERN WY INTO NERN NM...INSTABILITY
WILL BE WEAKER /MLCAPES 500-1500 J/KG/ THAN POINTS TO THE SE OWING
TO DRIER BOUNDARY LAYER CONDITIONS.  HOWEVER...THE PRESENCE OF STEEP
LOW TO MID LEVEL LAPSE RATES AND STRONGER VERTICAL SHEAR /30-40 KTS/
WILL SUPPORT SEVERE STORMS...INCLUDING THE POTENTIAL FOR A COUPLE
SUPERCELLS CAPABLE OF LARGE HAIL AND LOCALLY STRONG WIND GUSTS.

..MEAD.. 08/25/2006