STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWBC. VALID 191200Z - 201200Z THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM MCK RSL 45 NNW P28 30 S DDC 50 WSW GCK 35 WSW AKO 25 E CYS BFF 40 W LBF MCK. THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 ENE ECG 10 WSW FAY 30 SSE AHN AUO MEI JAN 45 ENE MLU 45 S PBF PBF MEM 55 NNE HSV LOZ 40 NW HTS 35 E DAY 35 ESE FWA 20 SSE JXN 20 S MTC ...CONT... MSS MSV 20 NNW ILG 25 SW DOV WAL. GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 55 WNW 3B1 35 WNW AUG 20 E PWM ...CONT... 30 E GLS 40 N HOU CLL AUS HDO 55 WSW HDO 25 S DRT ...CONT... 15 SSE IPL TRM 30 NNE DAG DRA P38 MLF PUC VEL CAG 30 E EGE 55 E GUC ALS 4SL 25 W ABQ ONM ALM CNM MAF 30 W ABI MWL DAL 40 NE DAL DUA ADM FSI LTS CDS 45 SE AMA 20 ENE LHX 40 NE DEN LAR RIW JAC 35 NNE IDA 25 SW DLN 30 S 3DU 50 N 3DU CTB HVR 30 SW GGW REJ 35 W EAR SLN EMP SGF ARG 30 NW DYR 35 NW HOP OWB BMG LAF 40 NNE CGX 15 WNW MBL 30 ENE PLN. --- SYNOPSIS --- UPPER AIR PATTERN ACROSS CONUS WILL FEATURE DEAMPLIFYING LONGWAVE RIDGE FROM NM-MN. WSWLY BELT OF FLOW OVER NRN ROCKIES/PACIFIC NW -- IN WAKE OF SHORTWAVE TROUGH NOW MAINLY OVER BC -- WILL BUCKLE WITH PASSAGE OF ANOTHER TROUGH ACROSS WA/ID/WRN MT LATE IN PERIOD. SLOW EWD MOTION AND FILLING OF SEASONALLY INTENSE CYCLONE NOW CENTERED OVER NRN IL WILL ANCHOR ERN STATES LONGWAVE TROUGH. AT SURFACE... ASSOCIATED COLD FRONT IS FORECAST TO CONTINUE MOVING EWD ACROSS OH VALLEY...AND A DECELERATING SWD MOTION OF ITS WRN PORTION IN OK/AR. --- OH VALLEY/ERN GREAT LAKES TO MS/AL --- OVERNIGHT MCS IS EXPECTED TO WEAKEN WITH SOME REMNANT CLOUD/PRECIP DEBRIS COVERING PARTS OF KY/OH AND POSSIBLY WRN PA EARLY MORNING. THIS SHOULD DIMINISH AND ALLOW STRONG DIURNAL HEATING TO OCCUR BENEATH ARC OF STRONGEST LARGE SCALE ASCENT ALOFT...AHEAD OF GREAT LAKES CYCLONE...SUPPORTING ADDITIONAL TSTM DEVELOPMENT DURING DAY. INCREASING VERTICAL SHEAR OVER THIS REGION WILL FAVOR DEVELOPMENT OF A FEW SUPERCELLS...AS WELL AS LINE SEGMENTS ALONG/AHEAD OF COLD FRONT. LARGE HAIL...WIND DAMAGE AND A FEW TORNADOES ARE POSSIBLE. A FEW SEVERE HAILSTORMS ARE POSSIBLE IN COLD CORE REGION OF CYCLONE AS WELL -- WHERE MID LEVEL LAPSE RATES MAY BE STEEPEST. FARTHER SW...LARGE SCALE FORCING IS EXPECTED TO WEAKEN BUT BOUNDARY LAYER THETAE WILL BE MUCH HIGHER FROM ERN TN ACROSS PORTIONS MS/AL. ORGANIZED MULTICELL TSTMS ARE POSSIBLE WITH AFTERNOON SBCAPE 2000- 3000 J/KG AND STRONG UPPER LEVEL FLOW...SUPPORTING POTENTIAL FOR DAMAGING DOWNDRAFTS AND LARGE HAIL. --- CAROLINAS/VA/MD REGION --- EXPECT RICH SURFACE MOISTURE AND DESTABILIZATION ALOFT BENEATH RIGHT ENTRANCE REGION OF UPPER JET MAX...COMBINED WITH WEAK CAPPING...PRIMARILY FRM BLUE RIDGE REGION EWD. THIS WILL SUPPORT WIDELY SCATTERED TO SCATTERED TSTMS -- SOME OF WHICH WILL BE ORGANIZED MULTICELLS WITH POTENTIAL FOR LARGE HAIL AND DAMAGING GUSTS. LINGERING CLOUDS/PRECIP FROM COMPLEX NOW OVER ERN GA/SRN SC MAY INHIBIT SIGNIFICANT HEATING FOR MUCH OF PERIOD -- ESPECIALLY NEAR COASTAL AREAS ALREADY STABILIZED BY LARGE AREA OF TSTMS THE PREVIOUS AFTERNOON. THEREFORE...SEVERE PROBABILITIES DECREASE EWD TOWARD ATLANTIC COAST OVER MOST OF REGION. --- CENTRAL HIGH PLAINS --- EXPECT MARGINAL LOW LEVEL MOISTURE -- MAINLY EVAPOTRANSPIRATIVE IN ORIGIN -- WITH NO DIRECT GULF RETURN AVAILABLE TO POST-FRONTAL SELYS OVER THIS REGION. STILL...50S TO LOW 60S SURFACE DEW POINTS NOW OBSERVED IN WRN KS SHOULD SPREAD NNWWD AND WWD SOMEWHAT -- WITH ADVECTION PARTIALLY OFFSETTING VERTICAL MIXING DURING DAY TO AID IN TSTM POTENTIAL. HIGH-BASED CONVECTION AND STEEP LAPSE RATES ARE EXPECTED...WITH MLCAPE 1000-1500 J/KG POSSIBLE AND WEAK CAPPING. STRONG DEEP-LAYER SPEED SHEAR AND LOW-MID LEVEL DIRECTIONAL SHEAR IS FORECAST BENEATH NW FLOW ALOFT. VERY DEVIANT SWWD STORM MOTIONS POSSIBLE IN AN REGIME OF WEAK LOW LEVEL FLOW...SUPPORTING POTENTIAL FOR A FEW TSTMS TO ROTATE. LARGE HAIL AND ISOLATED STRONG-SEVERE GUSTS POSSIBLE. --- WRN/SRN AZ --- CHANCES CONTINUE TO DECREASE FOR OVERNIGHT CONVECTION BEFORE 19/12Z TO STABILIZE MORNING AIR MASS ACROSS REGION...THEREFORE INTENSE INSOLATION AND SUFFICIENT LOW LEVEL MOISTURE MAY BE IN PLACE BY MID AFTERNOON FOR WIDELY SCATTERED TSTMS FORMING ON HIGHER TERRAIN. SOME MAY PRODUCE GUSTS NEAR SEVERE LEVELS. ..EDWARDS.. 08/19/01 PROBABILISTIC OUTLOOK MAPS ARE AVAILABLE ON THE SPC WEBSITE AT (LOWER CASE): HTTP://WWW.SPC.NOAA.GOV/PRODUCTS/OUTLOOK NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED FOR 1300Z
