ZCZC SPCSWODY1 ALL ACUS01 KWNS 251254 SPC AC 251254 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0754 AM CDT MON AUG 25 2003 VALID 251300Z - 261200Z THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 SE DTW 15 NW FDY 30 SSE CGX 30 WSW DBQ 20 WNW MHE 40 WNW PIR 30 ESE Y22 30 ENE BIS 65 NNE DVL GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 WNW CZZ 20 E RAL 20 S PMD 35 ESE FAT 55 NE MER 40 NW EKO 30 S MLD 40 NNE VEL 35 NNW LAR 35 NNE REJ 65 NNW MOT ...CONT... 25 W ERI 25 SE DUJ 15 ENE MRB SHD 20 ENE CRW 45 ENE LUK 15 N DNV 35 NW UIN 40 N SZL 40 N SGF 35 SE HRO 35 WSW MEM 30 E TUP 10 N RMG 40 SW HSS 35 NW HKY 25 SE GSO 25 SW SOP 20 W FLO 20 SSW CRE GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 ESE LNK 35 ESE GRI 35 SSW EAR 35 SE LAA 30 E TCC 55 SSE CVS 30 SSE LBB 30 S CDS 20 SSE END 30 W EMP 25 ESE LNK GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 NE 4OM 55 NW EAT 10 SW HQM ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ERN DAKOTAS ACROSS THE UPPER GREAT LAKES REGION... ...SYNOPSIS... FAST ZONAL FLOW ACROSS THE NRN CONUS ATTM WILL AMPLIFY SOMEWHAT THIS PERIOD AS UPPER LOW NOW OFF THE BRITISH COLUMBIA COAST MOVES EWD AND SECOND / LOW-AMPLITUDE SHORT-WAVE TROUGH MOVES ESEWD ACROSS THE CANADIAN PRAIRIE PROVINCES. THIS SECOND FEATURE AND ASSOCIATED MID-LEVEL JET STREAK WILL INFLUENCE THE SEVERE CONVECTIVE FORECAST ACROSS THE N CENTRAL CONUS. AT THE SURFACE...CONVECTIVELY-REINFORCED BAROCLINIC ZONE LYING ROUGHLY W-E FROM THE DAKOTAS EWD ACROSS MN / WI SHOULD LIFT SLOWLY NWD AS A WARM FRONT AHEAD OF COLD FRONT FORECAST TO MOVE SEWD ACROSS THE NRN PLAINS. THIS FRONT -- ASSOCIATED WITH AFOREMENTIONED SHORT-WAVE TROUGH / JET MAX -- IS EXPECTED TO EXTEND FROM THE UPPER GREAT LAKES SWWD ACROSS IA INTO SRN NEB / NRN KS BY THE END OF THE PERIOD. ...NRN PLAINS EWD INTO THE UPPER GREAT LAKES REGION... COMPLICATED FORECAST THIS PERIOD WITH ONGOING PRECIPITATION AND LATEST RAOBS / SURFACE DATA INDICATING LESS POTENTIAL FOR DESTABILIZATION ACROSS THE REGION THAN MODEL FORECASTS WOULD SUGGEST. STORMS CONTINUE ATTM INVOF SURFACE BOUNDARY ACROSS SERN MN / SRN WI...AS WELL AS ACROSS ERN ND INVOF WEAK IMPULSE AHEAD OF STRONGER UPPER TROUGH / JET MAX. ALTHOUGH SOME DECREASE IN CONVECTION IS POSSIBLE OVER THE NEXT SEVERAL HOURS...SCATTERED STORMS SHOULD CONTINUE INTO THE AFTERNOON. ALTHOUGH DEGREE OF DESTABILIZATION REMAINS A QUESTION...STORMS SHOULD INCREASE / REDEVELOP DURING THE AFTERNOON INVOF W-E BAROCLINIC ZONE ACROSS THE SRN GREAT LAKES REGION...AND ALSO AHEAD OF COLD FRONT WHICH SHOULD BE MOVING SEWD ACROSS THE DAKOTAS / NWRN MN. WITH BELT OF MODERATE TO STRONG MID-LEVEL FLOW ACROSS THIS REGION...STORMS SHOULD ORGANIZE / BECOME SEVERE...ALTHOUGH CONVECTIVE MODE REMAINS DIFFICULT TO DETERMINE ATTM. STRONGER LINEAR FORCING ALONG SEWD-MOVING COLD FRONT SUGGESTS THAT STORMS SHOULD BE MAINLY LINEAR WITH BOWING STRUCTURES ACROSS THE NRN GREAT LAKES REGION...PARTICULARLY INTO THE EVENING / OVERNIGHT. MEANWHILE... WEAKER FORCING FURTHER SOUTH MAY SUPPORT MORE ISOLATED / SUPERCELL STORMS. LARGE HAIL AND DAMAGING WINDS WILL LIKELY BE THE MAIN SEVERE THREATS...WITH GREATER HAIL THREAT ACROSS SRN PORTIONS OF THE RISK AREA AND GREATER / POTENTIALLY SIGNIFICANT WIND THREAT ACROSS NRN MN / NRN WI / UPPER MI. OVERNIGHT...STORMS SHOULD SPREAD EWD ACROSS THE REGION TOWARD SRN ONTARIO AS SHORT-WAVE TROUGH MOVES RAPIDLY EWD. ..GOSS.. 08/25/2003 ...NOTICE... FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3. THE INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED. $$ |