The SPC is forecasting ...an outbreak of severe thunderstorms is expected over parts of the central and southern plains this afternoon and tonight.... Please read the latest public statement about this event.
| Categorical Graphic |
|---|
|
| Probabilistic Tornado Graphic |
 |
 |
| Probabilistic Damaging Wind Graphic |
 |
 |
| Probabilistic Large Hail Graphic |
 |
 |
SPC AC 241700 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1200 PM CDT TUE APR 24 2007 VALID 241630Z - 251200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS CENTRAL AND ERN KS...SWRN MO...CENTRAL AND ERN OK...WRN AR AND NRN...CENTRAL AND SWRN TX.... ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDS THE MDT RISK AREA ACROSS THE CENTRAL AND SRN PLAINS INTO THE MIDDLE MS VALLEY.... ...SIGNIFICANT SEVERE WEATHER EPISODE IS EXPECTED FOR TODAY AND TONIGHT ACROSS PARTS OF THE SOUTHERN PLAINS... ...SYNOPSIS... LATEST IR/WATER VAPOR IMAGERY DEPICTS MID/UPPER LEVEL LOW OVER SERN CO THIS MORNING. SURFACE ANALYSIS SHOWS ATTENDANT LOW OVER THE SRN BORDER OF CO/KS WITH DRYLINE FEATURE THAT EXTENDS SEWD INTO NWRN OK THEN SWD ACROSS SWRN OK/NWRN TX INTO THE BIG BEND AREA OVER THE MIDDLE RIO GRANDE. ALSO...A WARM FRONT EXTENDS NEWD INTO N CENTRAL KS THEN EWD/SEWD THRU NWRN INTO E CENTRAL MO. MODELS TAKE THE MAIN MID/UPPER LEVEL LOW ESEWD TODAY AND INTO TONIGHT OVER SWRN KS/NWRN OK REFOCUSING THE SURFACE LOW INTO NWRN OK. THE OTHER MAIN FEATURE TO WATCH IS THE SECONDARY SHORTWAVE/VORTICITY MAX NOW MOVING INTO S CENTRAL NM. IT IS THIS FEATURE THAT THE MODELS FOCUS STRONG FORCING ALONG THE DRYLINE AND MOVING IT NEWD INTO NWRN TX/SWRN OK BY THIS EVENING. IMPRESSIONS AT THIS TIME ARE THAT THIS FORCING MAY PRODUCE AN AREA OF SIGNIFICANT SEVERE WEATHER ACROSS PARTS OF OK INTO NRN TX LATER THIS AFTERNOON AND EARLY TONIGHT. ...CENTRAL AND SOUTHERN PLAINS... STRONG THUNDERSTORMS ARE ALREADY OCCURRING OVER A SMALL PORTION OF N CENTRAL KS...BUT ALSO OVER SWRN INTO NWRN OK. THIS ACTIVITY IS JUST OFF THE DRYLINE NEAR THE AXIS OF MODERATE INSTABILITY WHERE MLCAPE IS BETWEEN 1500-2000 J/KG. OF COURSE...GIVEN THE CURRENT LOCATION OF THE MID/UPPER LEVEL LOW...STRONG LOW LEVEL JET OF 50 KT EXTENDS FROM EXTREME SRN TX NWD THRU NERN KS WITH GENERALLY SWLY MID LEVEL FLOW OF 60-70 KT ACROSS W TX. THUS...DEEP LAYER SHEAR VALUES OF 40-50 KT ARE PRESENT THROUGHOUT THE REGION SUPPORTIVE OF STRONG UPDRAFTS/SUPERCELLS. QUESTION WITH THE MODELS RIGHT NOW IS THE ANALYSIS THAT THERE IS A MERIDIONAL JET STREAK E OF THE MID/UPPER LEVEL LOW CIRCULATION WITH A DEEPENING FEATURE THAT IS PROGGED TO DRIFT JUST S OF E TOWARDS NWRN OK BY 25/00Z. ALL THE MODELS...ESPECIALLY THE GFS...BRING A MID LEVEL JET STREAK NEWD INTO NWRN TX THIS EVENING PLACING THE EXIT REGION OVER THIS REGION IN THE VICINITY OF THE DRYLINE AND THE WRN EDGES OF 40-50 KT LOW LEVEL FLOW. IF THIS SCENARIO COMES ABOUT...THEN THE SCENARIO WOULD INDICATE THE POTENTIAL FOR TORNADOES FROM CENTRAL OK SWD AND SWWD INTO PARTS OF CENTRAL TX. THEREFORE...AS SFC LOW MOVES INTO SWRN KS BY LATER THIS AFTERNOON... DRYLINE IS EXPECTED TO SURGE ENEWD INTO S CENTRAL OK/ N CENTRAL TX INTENSIFYING STORM ACTIVITY ACROSS THE AREA. MUCH OF THE ACTIVITY MAY ALREADY BE LINEAR WITH A FEW DISCRETE SUPERCELLS POSSIBLE JUST AHEAD OF THE LINE. SEVERE THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS OK INTO NWRN TX AND WILL SPREAD EWD THRU THIS AFTERNOON AND TONIGHT PRODUCING LARGE HAIL AND DAMAGING WINDS AS WELL AS A FEW STRONG TORNADOES. ..MCCARTHY/CORFIDI.. 04/24/2007 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z