SWODY1
SPC AC 051647
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1147 AM CDT SUN AUG 05 2007
VALID 051630Z - 061200Z
..THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN ROCKIES INTO THE
NRN HIGH PLAINS...
..THERE IS A SLGT RISK OF SVR TSTMS OVER THE DELMARVA REGION...
..THERE IS A SLGT RISK OF SVR TSTMS FROM ERN IA INTO WRN OH...
..NRN ROCKIES INTO NRN HIGH PLAINS...
WELL-DEFINED UPPER VORTICITY MAX OVER NRN CA IS EXPECTED TO CONTINUE
NEWD INTO NRN NV THIS AFTERNOON BEFORE LOSING AMPLITUDE AND
ACCELERATING NEWD INTO CNTRL/ERN MT LATE TONIGHT. WATER VAPOR
IMAGERY SHOWS DEVELOPING AREA OF CLOUDS AND INCREASING MID/UPPER
LEVEL MOISTURE ASSOCIATED WITH LARGE SCALE ASCENT AHEAD OF THE
SYSTEM OVER ERN OREGON INTO SRN/CNTRL ID AND SWRN MT. IN
ADDITION...MONSOON MOISTURE IS SPREADING NWD FROM AZ/UT INTO WY
WITHIN SLY DEEP LAYER FLOW ON THE WRN PERIPHERY OF THE SRN PLAINS
HIGH.
AS THE UPPER FEATURE MOVES NEWD AND INTERACTS WITH AN ENVIRONMENT
CHARACTERIZED BY INCREASING MOISTURE AND STEEP LAPSE
RATES...CONVECTION IS LIKELY TO INCREASE THIS AFTERNOON AND EVENING
OVER PARTS OF SERN ID...SWRN MT AND WRN WY. ALTHOUGH CLOUDS WILL
INHIBIT HEATING IN SOME AREAS...BREAKS IN CLOUD COVER WILL PERMIT
REGIONS OF STRONGER HEATING/DESTABILIZATION TO OCCUR. SWLY MID
LEVEL WINDS OF 40-45 KT WILL CONTRIBUTE TO SUFFICIENT DEEP LAYER
SHEAR /40-50 KT IN THE LOWEST 6 KM/ TO ENHANCE STORM ORGANIZATION
AND INTENSITY INCLUDING THE POSSIBILITY OF ISOLATED SUPERCELLS.
DAMAGING WIND GUSTS AND LARGE HAIL WILL BE POSSIBLE WITH STRONGER
STORMS.
STRONG/SEVERE CONVECTION IS EXPECTED TO SPREAD ENEWD ACROSS PARTS OF
THE NRN ROCKIES TONIGHT AS THE UPPER SYSTEM/ATTENDANT JET STREAK
PROGRESS ENEWD TOWARD THE NRN HIGH PLAINS. STRONG WIND GUSTS WILL
BE THE PRIMARY THREAT WITH THIS ACTIVITY...WITH POTENTIAL FOR AN
INCREASE IN THUNDERSTORM COVERAGE LATER TONIGHT OVER PARTS OF ERN MT
AND THE WRN DAKOTAS AS LOW LEVEL UPSLOPE FLOW STRENGTHENS ACROSS THE
AREA. INCREASING MOISTURE ASSOCIATED WITH THE NOCTURNAL LOW LEVEL
JET OVER THE HIGH PLAINS COUPLED WITH CONTINUED FAVORABLE DEEP LAYER
SHEAR MAY RESULT IN AN INCREASE IN AN ELEVATED SEVERE HAIL THREAT
LATE IN THE PERIOD.
DURING THE AFTERNOON AND EVENING...ISOLATED STRONG/SEVERE STORMS MAY
ALSO DEVELOP OVER PARTS OF WRN SD ALONG TRAILING PART OF SURFACE
COLD FRONT. THIS ACTIVITY SHOULD WEAKEN AFTER SUNSET.
..DELMARVA REGION...
STRONG HEATING IS OCCURRING OVER THE AREA WITH SURFACE TEMPERATURES
IN THE 85-90F RANGE...AND WITH DEW POINTS IN THE LOW/MID 70S...THE
ENVIRONMENT IS BECOMING MODERATELY UNSTABLE WITH MLCAPE AROUND 2000
J/KG. ALTHOUGH LARGE SCALE FORCING IS NOT PARTICULARLY
STRONG...WEAKENING CAP COUPLED WITH CONVERGENCE ALONG FRONT/LEE
TROUGH AND SEA BREEZE BOUNDARIES SHOULD BE SUFFICIENT FOR PARCELS TO
REACH THE LFC OVER THE NEXT FEW HOURS. VERTICAL SHEAR OF 30-35 KT
ACROSS THE REGION WILL PROMOTE STORM ORGANIZATION WITH STRONGER
CELLS CAPABLE OF PRODUCING HAIL AND STRONG WIND GUSTS. SEVERE
THREAT SHOULD DIMINISH BY EVENING.
..ERN IA INTO WRN OH...
COMPLEX SURFACE PATTERN HAS EVOLVED THROUGH THE MORNING WITH SURFACE
WARM FRONT LIFTING NWD WHILE CONVECTIVELY INDUCED BOUNDARIES REMAIN
IN PLACE IN THE WARM SECTOR. WATER VAPOR IMAGERY SUGGESTS VORTICITY
MAX IS MOVING ESEWD ACROSS SRN WI...AND THIS FEATURE MAY ENHANCE
CONVECTIVE POTENTIAL WITHIN CLEAR SLOT EXTENDING FROM EAST CENTRAL
IA INTO NRN IL. STORMS WOULD THEN MOVE EWD/ESEWD ALONG THE SRN EDGE
OF THE STRONGER WLY FLOW ALOFT. WARM MID LEVEL TEMPERATURES/WEAKER
LAPSE RATES WILL LESSEN HAIL THREAT BUT STRONGER CELLS MAY BE
CAPABLE OF PRODUCING DAMAGING WIND GUSTS.
.WEISS/CROSBIE.. 08/05/2007
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