ZCZC SPCSWODY1 ALL ACUS01 KWNS 221605 SPC AC 221601 STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWNS. VALID 221630Z - 231200Z THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING ACROSS PORTIONS OF NERN FL...SERN GA...ERN NC AND SC AND SERN VA. THIS AREA IS TO THE RIGHT OF A LINE FROM 45 NNW DAB PIE ...CONT... 20 WNW CTY 55 SSW AGS 20 E GSO 10 NNW ORF. THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 15 NNE MLB 20 W FMY ...CONT... 30 ESE TLH 40 ENE ABY ATL 30 N BHM 30 NE MSL CKV 30 ENE BWG 25 W LOZ 25 SSE LOZ 25 NNW HSS 15 NNE HKY 40 SE PSK 35 NNW RIC 25 ENE SBY. GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 SSW TLH ABY 20 NE CSG 30 W AUO 15 SW BHM 30 SW MSL 40 ESE MKL 50 WSW OWB 35 S BMG 35 W HLG 15 SSW SYR 40 ENE UCA GFL 15 WNW GON. GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 SSW CAO 40 NNW PUC 30 ESE PIH 15 SSE BZN 50 WSW GCC 15 SSW AIA 45 W GCK 20 SSW CAO. ...SYNOPSIS... POWERFUL UPPER TROUGH CROSSING THE LOWER MS VALLEY EARLY TODAY WILL EJECT NEWD ACROSS THE TN VALLEY...AND THEN PHASE WITH NRN STREAM SHORTWAVE TROUGH MOVING EAST FROM THE CNTRL U.S. DEEPENING 988MB CYCLONE...CURRENTLY OVER WRN TN ...WILL TRACK INTO ERN KY TODAY...AND INTO WRN NY BY EARLY SUNDAY. COLD FRONT EXTENDS SWD THRU WRN AL INTO GULF WITH PRE-FRONTAL SQUALL LINE FROM WRN CAROLINAS TO ERN FL PANHANDLE MOVING RAPIDLY NEWD. WARM FRONT EXTENDS EWD ACROSS NC WILL MOVE INTO SRN VA LATER THIS AFTERNOON. ...FL/GA THE CAROLINAS AND SERN VA... VERY MOIST AND MODESTLY UNSTABLE WARM SECTOR SPREADING NEWD AHEAD OF SQUALL LINE INTO NC AND SERN VA THIS AFTERNOON. WHILE CAPES GENERALLY 1000 J/KG OR LESS AND LAPSE RATES AROUND 6C/K...VERY STRONG DEEP LAYER SHEAR SUPPORTS WIND DAMAGE WITH SQUALL LINE. GIVEN THE STRONG SHEAR PROFILES...ISOLATED TORNADOES ALSO LIKELY WITH BOWING SEGMENTS IN LINE AND ANY DISCRETE STORMS THAT CAN DEVELOP AHEAD OF LINE. ACTIVITY WILL LIKELY MOVE OFFSHORE THIS EVENING WITH DIMINISHING THREAT OF SEVERE. ...TN VALLEY... WHILE SQUALL LINE HAS MOVED EAST OF AL...RESIDUAL AXIS OF STRONGER INSTABILITY REMAINS SITUATED WITHIN RECOVERING WARM SECTOR FROM ERN AL AHEAD OF COLD FRONT NWD INTO MIDDLE TN. A CLUSTER OF STRENGTHENING TSTMS ON THE LEADING EDGE OF DPVA ASSOCIATED WITH PRIMARY VORTICITY MAX WAS MOVING NEWD TOWARD THE INSTABILITY AXIS OVER NRN AL/MIDDLE TN. THIS ACTIVITY WILL LIKELY CONTINUE TO BE FUELED BY VERY STRONG LARGE SCALE FORCING FOR ASCENT AND DESTABILIZATION WITHIN THE DRY SLOT ACROSS MIDDLE TN. GIVEN COLD POOL ALOFT AND STRONG SHEAR EXPECT A FEW OF THESE STORMS COULD PRODUCE HAIL AND HIGH WINDS AS THE CLUSTER MOVES NEWD ACROSS TN AND INTO SRN KY BY AFTERNOON. ..HALES.. 02/22/03 NNNN |