STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK
DAY 2 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWI47 KWNS.
VALID 261200Z - 271200Z
THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM
25 SSW ILM SOP 30 E DAN RIC WAL.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 85 E ELO 15 S EAU
25 SE MCW 35 NNE MHK 15 NE HLC 20 ESE CYS 30 N RIW 30 NNE IDA BNO
EUG OLM 60 E BLI.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 S TLH 45 ESE AHN
55 ENE BWG 25 WSW CMH 25 ESE PSB POU 25 SE AUG.
...SYNOPSIS...
SHORTWAVE TROUGH OVER THE WRN CAROLINAS AT THE BEGINNING OF THE
PERIOD WILL LIFT NEWD OFF THE MIDDLE ATLANTIC COAST BY SATURDAY
EVENING. UPSTREAM SHORTWAVE TROUGH AND ASSOCIATED MID/UPPER-LEVEL
JET STREAK WILL PROGRESS FROM THE GREAT BASIN INTO THE NRN
PLAINS...TO THE S OF AMPLIFIED BLOCKING PATTERN IN PLACE ACROSS
CANADA. AT THE SURFACE...LOW OVER VA WILL WEAKEN AS IT RAPIDLY
LIFTS NEWD INTO NEW ENGLAND WHILE TRAILING COLD FRONT SWEEPS EWD
THROUGH THE MIDDLE ATLANTIC AND SERN U.S. STATES. FARTHER W...LOW
AND ASSOCIATED FRONTAL SYSTEM WILL MOVE EWD OUT OF THE NRN ROCKIES
AND ACROSS THE NRN PLAINS.
...VA/NC...
STEEP MID-LEVEL LAPSE RATES /7-8 C/KM/ ATOP SURFACE DEWPOINTS IN
THE 60S WILL CONTRIBUTE A MODERATELY UNSTABLE AIRMASS WITH MLCAPES
APPROACHING 1000-1500 J/KG AHEAD OF THE SURFACE LOW AND ASSOCIATED
COLD FRONT. DEEP-LAYER SHEAR ON THE ORDER OF 40-50 KTS WILL SUPPORT
ISOLATED STRONG/SEVERE TSTMS THROUGH THE AFTERNOON HOURS...MAINLY
ACROSS ERN PARTS OF VA/NC. LARGE HAIL WILL BE THE PRIMARY SEVERE
WEATHER THREAT GIVEN THE COLD MID-LEVEL TEMPERATURES/LOW WET-BULB
ZERO HEIGHTS. ACTIVITY SHOULD MOVE OFFSHORE BY LATE AFTERNOON/
EVENING.
...FL...
STRONG TSTMS MAY BE ONGOING AT THE BEGINNING OF THE FORECAST ACROSS
THE CNTRL PENINSULA AS SURFACE DEWPOINTS AROUND 70F AND MID-LEVEL
LAPSE RATES OF 6.5-7 C/KM CONTRIBUTE TO MLCAPES OF 2000-2500 J/KG.
ALTHOUGH ISOLATED LARGE HAIL/DAMAGING WINDS ARE POSSIBLE...
DIMINISHING LOW-LEVEL CONVERGENCE AND WEAKENING DEEP-LAYER SHEAR
SUGGEST THAT POTENTIAL AREAL COVERAGE IS TOO LIMITED TO INCLUDE A
SLIGHT RISK ATTM.
...DAKOTAS/MN...
LOW-LEVEL MOISTURE WILL REMAIN QUITE LIMITED AHEAD OF SURFACE LOW
AND COLD FRONT MOVING THROUGH THE REGION. HOWEVER...STEEP MID-LEVEL
LAPSE RATES /7-8 C/KM/ AND INCREASED FORCING FOR LARGE-SCALE ASCENT
AHEAD OF APPROACHING SHORTWAVE TROUGH MAY BE SUFFICIENT FOR
ISOLATED TSTM DEVELOPMENT MAINLY DURING THE EVENING AND OVERNIGHT
PERIOD. SMALL HAIL AND GUSTY WINDS WILL BE POSSIBLE IN THE
STRONGEST STORMS.
..MEAD.. 04/25/03
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED FOR 0800Z
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