ZCZC SPCSWODY1 ALL ACUS01 KWNS 170045 SPC AC 170044 STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWNS. VALID 170100Z - 171200Z NO SVR TSTM AREAS FCST. GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 ENE CMX 60 N EAU OTM MKC ICT LBL 15 E P07 50 NW LRD 50 SSW SPS 10 NE FSI UNO 15 SSW LAF 20 WSW CLE 25 ENE PIT 25 NW RIC 25 SE ORF ...CONT... 20 SW FHU 25 NNW SOW 60 NNW GUP 40 ESE U24 50 SSE ELY 25 ENE TPH 35 SSW BIH 50 NNE SAC 20 E SVE 50 N WMC 30 ESE BOI 35 NE BKE 20 W S80 50 NE FCA. ...NRN PLAINS... COLD FRONT...CURRENTLY EXTENDING FROM ERN ND SWWD INTO CNTRL SD AND THEN CNTRL WY...WILL PROGRESS SEWD THROUGH THE AREA AHEAD OF SHORTWAVE TROUGH CURRENTLY OVER CNTRL ND. LOW-LEVEL CONVERGENCE INVOF THIS FRONT HAS ALLOWED DEWPOINTS TO INCREASE LOCALLY INTO THE MID 60S FROM THE RED RIVER VALLEY SWWD INTO CNTRL SD. THIS MOISTURE IN CONJUNCTION WITH STEEP MID-LEVEL LAPSE RATES ARE CONTRIBUTING TO A MODERATELY UNSTABLE AIRMASS FROM ERN NEB NWD ACROSS THE ERN DAKOTAS/WRN MN WITH MLCAPES OF 1000-2000 J/KG. TSTMS SHOULD PERSIST OVERNIGHT ALONG AND E OF FRONTAL BOUNDARY INTO MN. ALTHOUGH A BAND OF 25-30KT MID-LEVEL WINDS WILL ACCOMPANY THE SHORTWAVE TROUGH EWD ACROSS ND INTO NRN MN...IT APPEARS THAT THE OVERALL SEVERE WEATHER THREAT WILL BE LIMITED BY THE RELATIVE WEAKNESS OF DEEP-LAYER SHEAR. ISOLATED LARGE HAIL/DAMAGING WINDS WILL REMAIN POSSIBLE WITH THE STRONGEST CELLS OVERNIGHT. ...CNTRL/SRN ROCKIES... STEEP-MID LEVEL LAPSE RATES AND SUFFICIENT BOUNDARY LAYER MOISTURE HAVE SUSTAINED CLUSTERS OF STRONG TSTMS EARLY THIS EVENING FROM CNTRL WY SWD INTO CNTRL/ERN NM. ALTHOUGH SHEAR PROFILES ARE RELATIVELY WEAK...ISOLATED LARGE HAIL AND DAMAGING DOWNBURSTS WILL REMAIN POSSIBLE FOR THE NEXT COUPLE OF HOURS PRIOR TO BOUNDARY- LAYER COOLING/STABILIZATION. ...TN VALLEY INTO THE SERN U.S... QUASI-STATIONARY FRONTAL SYSTEM EXTENDS FROM CNTRL NC WWD TO A WEAK SURFACE LOW OVER MIDDLE TN WITH TRAILING PORTION OF FRONT STRETCHING INTO NRN MS/SRN AR. RICH LOW-LEVEL AIRMASS /DEWPOINTS IN THE 70S/ ALONG AND S OF THIS BOUNDARY IS CONTRIBUTING TO MLCAPES OF 1000-2000 J/KG FROM CNTRL KY/MIDDLE TN S AND E ACROSS THE CNTRL GULF COAST INTO THE SERN U.S.. ALTHOUGH MUCH OF THE ONGOING TSTM ACTIVITY IS EXPECTED TO WEAKEN RELATIVELY QUICKLY...THE POTENTIAL FOR ISOLATED STRONG/SEVERE STORMS MAY CONTINUE FOR THE NEXT FEW HOURS INVOF SURFACE FRONT AND AHEAD OF SHORTWAVE TROUGH LIFTING NEWD THROUGH TN. DAMAGING DOWNBURSTS WILL BE THE PRIMARY SEVERE WEATHER THREAT. ..MEAD.. 06/16/03 NNNN |