ZCZC SPCSWODY1 ALL ACUS01 KWNS 061223 SPC AC 061223 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0723 AM CDT WED AUG 06 2003 VALID 061300Z - 071200Z THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 55 N GGW 45 SSW REJ 30 NNW CDR 20 NW SNY CYS 35 SSW DGW SHR 40 S BIL WEY 25 N SUN 55 E BKE 30 ENE ALW 30 NNE 63S THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM JAN 45 SE ESF 20 S POE LFK 20 ESE TYR 50 SW JBR 15 SW UNO TBN 45 SSW STL MDH 25 W BWG BNA 10 W HSV CBM JAN GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 NE ISN 30 E DIK 45 SE Y22 50 ESE PHP MHN MCK 50 SSW P28 FSI 20 NW FTW 45 NNW GGG HOT SZL 35 ESE OMA 45 ESE INL ...CONT... 45 E MQT 35 SW SBN DAY 30 E SSU 15 ESE ORF ...CONT... 10 SW GLS 50 SSW CLL JCT 15 NNW INK GDP 80 SSW GDP ...CONT... 45 S TUS 50 SW SOW 55 WSW GUP 55 NNW GUP CAG 50 WSW LAR 45 SE WRL COD SUN 50 SSE BKE BNO MHS 45 W MHS 35 NNW 4BK GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 SSW JFK 10 SSE IPT 30 NE CLE ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE LOWER/MID MS AND WRN TN VALLEYS... ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF THE NRN ROCKIES/HIGH PLAINS... ...SYNOPSIS... LONG WAVE PATTERN WILL REMAIN QUASI-STATIONARY WITH UPPER TROUGHS IN THE EAST AND WEST CONUS...AND A RIDGE SANDWICHED IN BETWEEN ACROSS THE ROCKIES. WITHIN THE ERN U.S TROUGH...A SHORTWAVE TROUGH WILL MOVE SEWD FROM IL INTO WRN KY DURING THE DAY...WHILE ANOTHER SYSTEM SHIFTS FROM SRN NY NWD INTO ME. WEAK COLD FRONT/TROUGH EXTENDING FROM NY SWWD INTO THE TX PANHANDLE WILL DRIFT SLOWLY SEWD DURING THE PERIOD. ...SERN MO AND WRN TN VALLEY AREA... ISOLATED STORMS ARE CURRENTLY LOCATED IN ERN MO IN ASSOCIATION WITH UPPER TROUGH. STORMS SHOULD MOVE/DEVELOP SEWD INTO THE REGION THIS AFTERNOON AS UPPER TROUGH MOVES SEWD. AN ISOLATED SEVERE STORM OR TWO IS POSSIBLE IN ERN MO THIS MORNING...BUT THREAT IS EXPECTED TO INCREASE THIS AFTERNOON AS SYSTEM ENCOUNTERS STRONGER INSTABILITY. THE INSTABILITY COMBINED WITH DYNAMICAL FORCING AND 25-30 KT DEEP LAYER SHEAR SHOULD BE SUFFICIENT FOR STORMS WITH HAIL AND WIND DAMAGE DURING THE AFTERNOON/EARLY EVENING HOURS. ...LOWER MS RIVER VALLEY... WARM ADVECTION HAS AIDED IN STORMS OVERNIGHT...BUT THIS CONVECTION SHOULD DIMINISH AS THE WARM ADVECTION WEAKENS. SKIES SHOULD CLEAR FROM THE WEST AND AS TEMPERATURES WARM INTO THE 90S THIS AFTERNOON...STORMS MAY REDEVELOP ALONG THE REMNANT CONVECTIVE OUTFLOW BOUNDARY/SURFACE TROUGH AS DIFFLUENCE STRENGTHENS ALOFT. AREA WILL BE LOCATED NEAR 850 THERMAL RIDGE AND STEEP LAPSE RATES WILL RESULT IN MODERATE TO STRONG INSTABILITY. STORMS INITIATION MAY BE INHIBITED BY WARMING ALOFT AS 500 MB TEMPERATURES ARE FORECAST TO RANGE FROM -2 TO -4C. HOWEVER...IF STORMS DO DEVELOP...STRONG LOW LEVEL LAPSE RATES AND 35 KT NWLY MID LEVEL WINDS WOULD BE FAVORABLE FOR DAMAGING WINDS. ...NRN ROCKIES... A SHORTWAVE TROUGH IS EVIDENT ON WV IMAGERY MOVING NEWD THROUGH SOUTH CENTRAL ORE. LARGE SCALE ASCENT AHEAD OF THIS FEATURE AND HEATING SHOULD INITIATE THUNDERSTORMS ACROSS ID/WRN MT THIS AFTERNOON. STEEP LASE RATES AND 35-40 KT SWLY MID LEVEL WINDS WILL RESULT IN SUFFICIENT INSTABILITY AND SHEAR FOR A FEW SUPERCELLS...WHICH WILL ENHANCE THE HAIL AND WIND THREAT. ...NRN HIGH PLAINS... UPSLOPE ELY BOUNDARY LAYER FLOW WILL MAINTAIN MID/UPPER 50 DEWPOINTS AND WITH HEATING...MLCAPES SHOULD RANGE FROM 1500 TO 2000 J/KG. A FORECAST OF STRONGLY VEERING WIND PROFILES RESULTS IN STRAIGHT LINE HODOGRAPHS...INDICATIVE OF POSSIBLE OF SPLITTING SUPERCELLS. HOWEVER...FORECAST SOUNDINGS INDICATE THE UPDRAFTS WILL BE ROOTED ABOVE 700 MB WITH HAIL THE MAIN THREAT. ...CENTRAL PLAINS... MODERATE INSTABILITY AND LIFT NEAR THE HIGHER TERRAIN MAY RESULT IN A FEW STORMS TO DEVELOP THIS AFTERNOON. HOWEVER...THE RIDGE AXIS ALOFT IS EXPECTED TO DAMPEN THE NUMBER OF STORMS AND THEIR INTENSITY. ...ERN TN VALLEY REGION... AS TROUGH IN IL APPROACHES THE AREA LATER IN THE DAY...STORMS MAY INTENSIFY. HOWEVER...STORM ORGANIZATION WILL BE MARGINAL FOR SEVERE WEATHER...GIVEN THE FORECAST OF WEAK SHEAR AND POOR MID LEVEL LAPSE RATES. ...GA/CAROLINAS/MID-ATLANTIC STATES... MAIN CONVECTION ASSOCIATED WITH LOWER OH VALLEY SHORTWAVE TROUGH SHOULD REMAIN WEST OF THE AREA THROUGH THE MAX HEATING PERIOD. ALTHOUGH MODERATE INSTABILITY WILL BE PRESENT...LAPSE RATES AND SHEAR WILL BE WEAK. GIVEN THESE PARAMETERS AND LACK OF DYNAMICAL FORCING...THREAT OF SEVERE STORMS APPEARS LOW. ...NRN NY/NEW ENGLAND... SHORTWAVE TROUGH IN PA WILL MOVE NEWD ACROSS THE AREA DURING THE AFTERNOON HOURS. DESPITE THE STRONG FLOW ALOFT...A WIND THREAT WILL BE LIMITED BY A NEARLY SATURATED AIR MASS AND SMALL DIURNAL WARMING. ..IMY.. 08/06/2003 ...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. $$ |