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 201603 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1103 AM CDT MON JUN 20 2011 VALID 201630Z - 211200Z ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER PORTIONS OF EASTERN NEB...WESTERN IA...SOUTHEAST SD...EAST KS... NORTHWEST MO SWD THROUGH CENTRAL OK...... ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL/SOUTHERN PLAINS EASTWARD TO THE OH VALLEY...THEN SOUTHEASTWARD TO THE CAROLINAS... ...CENTRAL/SRN PLAINS... UNSEASONABLY STRONG UPPER LOW MOVING FROM CURRENT POSITION SE CO NEWD ACROSS WRN KS INTO SRN NEB BY 12Z TUE. 60-70KT 500MB JET MAX WITH ASSOCIATED STRONG ASCENT/DIVERGENCE SPREADING NEWD FROM CENTRAL HIGH PLAINS ACROSS KS INTO NEB THIS AFTERNOON. SURFACE LOW OVER W-CENTRAL KS WILL MOVE SLOWLY NNEWD INTO SRN NEB. THE DRY LINE EXTENDING FROM THE LOW SWD THRU FAR WRN OK/SWRN TX WILL SHIFT EWD BY MID AFTERNOON TO EXTEND ON A N/S AXIS VICINITY THE I-35 CORRIDOR. VERY STRONG SLY WINDS AHEAD OF DRY LINE WILL WRAP NWWD THE MOIST AND UNSTABLE AIR MASS TO N OF SURFACE LOW INTO CENTRAL NEB. THE STRONG LARGE SCALE ASCENT COUPLED WITH THE POST FRONTAL MOIST NLY FLOW WRN KS THIS AM HAS GENERATED ELEVATED SEVERE THUNDERSTORMS. BY MID AFTERNOON CONDITIONS WILL RAPIDLY DEVELOP TO SUPPORT AN OUTBREAK OF SEVERE THUNDERSTORMS BOTH ALONG THE DRY LINE AND IN THE VERY FAVORABLE SHEAR AND LARGE SCALE ASCENT REGION TO THE N/NE OF THE SURFACE LOW ACROSS NEB. THE STRONGLY SHEARED PROFILES AHEAD OF THE SURFACE LOW OVER ERN NEB COUPLED WITH MLCAPES CLIMBING TO AOA 2000 J/KG EXPECTED TO SUPPORT TORNADIC SUPERCELL DEVELOPMENT BY MID/LATE AFTERNOON. THERE IS THE POTENTIAL OF STRONG TORNADOES GIVEN THE ENVIRONMENT THAT WILL BE IN PLACE. DOWN THE DRY LINE SCATTERED SUPERCELLS WILL DEVELOP AS THE CAP BREAKS BY MID/LATE AFTERNOON. BY THAT TIME MLCAPES WILL HAVE CLIMBED TO AOA 2500 J/KG SWD TO THE OK/TX BORDER WHICH WHEN COUPLED WITH THE PRESENCE OF THE MID LEVEL JET MAX AND VERY STEEP LAPSE RATES WILL RESULT IN A VERY LARGE HAIL POTENTIAL ALONG WITH DAMAGING DOWNBURST WINDS. IT NOW APPEARS COVERAGE OF BOTH THE HAIL AND WIND WILL BE SUFFICIENT TO UPGRADE THE RISK TO MDT AS FAR S AS THE OKC AREA . THERE WILL ALSO BE THE POTENTIAL FOR TORNADOES GIVEN THE 50-60 KT OF SHEAR. FURTHER S INTO NCENTRAL TX THE EXPECTED COVERAGE WILL BE LESS BUT THERE IS STILL POTENTIAL OF VERY LARGE HAIL AND DAMAGING DOWNBURSTS. 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. ...OH VALLEY TO CAROLINAS... A BAND OF MODERATELY STRONG MID LEVEL WINDS EXTENDS FROM IND/OH INTO THE CAROLINAS TODAY. THE PRIMARY LOW LEVEL INSTABILITY GRADIENT WILL ALSO RUN ALONG THIS CORRIDOR. MULTIPLE CLUSTERS OF STRONG TO SEVERE THUNDERSTORMS ARE LIKELY OVER THIS REGION THIS AFTERNOON AND TONIGHT. DAMAGING WINDS WOULD BE THE MAIN THREAT ASSOCIATED WITH BOWING SEGMENTS...ALTHOUGH THE STRONGEST STORMS COULD ALSO PRODUCE LARGE HAIL. ..HALES/HURLBUT.. 06/20/2011 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z