The SPC is forecasting ...severe thunderstorms expected over parts of the central plains this afternoon and tonight.... Please read the latest public statement about this event.
| Categorical Graphic |
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| Probabilistic Tornado Graphic |
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| Probability of a tornado within 25 miles of a point. Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point. |
| Probabilistic Damaging Wind Graphic |
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| Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point. Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point. |
| Probabilistic Large Hail Graphic |
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| Probability of hail 1" or larger within 25 miles of a point. Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point. |
SPC AC 201238 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0738 AM CDT MON JUN 20 2011 VALID 201300Z - 211200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER PORTIONS OF EASTERN NEB...WESTERN IA...SOUTHEAST SD...NORTHEAST KS...AND NORTHWEST MO... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL/SOUTHERN PLAINS EASTWARD TO THE OH VALLEY...THEN SOUTHEASTWARD TO THE CAROLINAS... ...CENTRAL PLAINS... MORNING WATER VAPOR LOOPS SHOW A LARGE UPPER TROUGH MOVING ACROSS THE WESTERN STATES...WITH AN EMBEDDED SMALLER IMPULSE ROTATING ACROSS NM. THIS SHORTWAVE TROUGH WILL EJECT INTO THE CENTRAL/SOUTHERN PLAINS THIS AFTERNOON HELPING TO INITIATE THUNDERSTORMS. A DEEP SURFACE LOW NOW OVER CENTRAL KS WILL MOVE VERY SLOWLY NORTHEASTWARD...WITH EASTERLY LOW LEVEL WINDS BEING MAINTAINED NEAR AND NORTHEAST OF THE LOW ACROSS EASTERN NEB/NORTHEAST KS/WESTERN IA/NORTHWEST MO. AMPLE LOW LEVEL MOISTURE WILL BE IN PLACE BY AFTERNOON WITH DEWPOINTS WELL INTO THE 60S AND MLCAPE VALUES OF 2500+ J/KG. INCREASING LARGE SCALE FORCING FOR ASCENT WILL OVERSPREAD THIS AREA BY 21Z...LEADING TO SCATTERED SUPERCELL THUNDERSTORMS. A MID LEVEL DRY SLOT IS FORECAST TO NOSE INTO SOUTHEAST NEB...WHICH IS REFLECTED IN THE OUTLOOK AREAS. HOWEVER...AREAS JUST NORTH AND EAST OF THE DRY SLOT WILL HAVE THE GREATEST POTENTIAL FOR INTENSE STORMS CAPABLE OF VERY LARGE HAIL AND A FEW TORNADOES. UPSCALE ORGANIZATION OF ONE OR MORE CLUSTERS IS ONCE AGAIN POSSIBLE TONIGHT WITH THE RISK OF WIDESPREAD DAMAGING WINDS AS STORMS SPREAD INTO IA/MO. ...KS/OK/TX... FARTHER SOUTH...A DRYLINE WILL EXTEND FROM THE LOW IN KS INTO CENTRAL OK AND WESTERN NORTH TX. HOT AND HUMID CONDITIONS WILL DEVELOP ALONG AND EAST OF THE DRYLINE WITH TEMPERATURES IN THE UPPER 90S AND MLCAPE VALUES OVER 3000 J/KG. ALL MODEL GUIDANCE IS CONSISTENT IN DEVELOPING A BAND OF STRONG THUNDERSTORMS THIS AFTERNOON FROM EASTERN KS INTO CENTRAL OK. FORECAST SOUNDINGS SHOW SUPERCELL WIND PROFILES...COUPLED WITH VERY STEEP LOW LEVEL LAPSE RATES AND LARGE SURFACE T-TD SPREADS. THIS COMBINATION MAY RESULT IN A PERIOD OF SIGNIFICANT HAIL AND WIND POTENTIAL DURING THE LATE AFTERNOON TO MID EVENING PERIOD. THIS AXIS MAY REQUIRE AN UPGRADE TO MODERATE RISK IN LATER UPDATES. ...OH VALLEY TO CAROLINAS... A BAND OF MODERATELY STRONG MID LEVEL WINDS WILL EXTEND FROM IND/OH INTO THE CAROLINAS TODAY. THE PRIMARY LOW LEVEL INSTABILITY GRADIENT WILL ALSO RUN ALONG THIS CORRIDOR. WHILE DETAILS ARE HARD TO GATHER...IT APPEARS LIKELY THAT MULTIPLE CLUSTERS OF STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE OVER THIS REGION THIS AFTERNOON AND TONIGHT. DAMAGING WINDS WOULD BE THE MAIN THREAT...ALTHOUGH THE STRONGEST STORMS COULD ALSO PRODUCE LARGE HAIL. ..HART/ROGERS.. 06/20/2011 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z