The SPC is forecasting ...severe thunderstorms with widespread damaging winds and several tornadoes expected over parts of the lower ohio valley...mid south...and lower mississippi valley through tonight.... Please read the latest public statement about this event. View What is a Watch? clip.
| 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 300053 DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0653 PM CST TUE JAN 29 2013 VALID 300100Z - 301200Z ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF FAR NE TX...NRN LA...AR...NW MS...WRN TN...SE MO...SRN IL...FAR SW IND AND WRN KY... ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN PLAINS....ARKLATEX....LOWER TO MID MS VALLEY AND OH VALLEY... ...LOWER TO MID MS VALLEY... THE LATEST WATER VAPOR IMAGERY SHOWS AN UPPER-LEVEL TROUGH MOVING EWD INTO THE SRN PLAINS. AN 80 TO 100 KT MID-LEVEL JET IS CURRENTLY EJECTING NEWD ACROSS THE SRN PLAINS. THIS ALONG WITH A STRENGTHENING LOW-LEVEL JET WILL ENABLE DEEP LAYER SHEAR TO CONTINUE TO INCREASE ACROSS THE LOWER TO MID MS VALLEY THIS EVENING. THE STRENGTHENING SHEAR COMBINED WITH INCREASING LIFT ASSOCIATED WITH A BAND OF STRONG LARGE-SCALE ASCENT WILL HELP A SQUALL-LINE TO CONTINUE TO ORGANIZE. MODEL FORECASTS STRONGLY INTENSIFY THE LINE LATE THIS EVENING DRIVING A NEARLY CONTINUOUS LINEAR MCS ACROSS THE LOWER TO MID MS VALLEY AND INTO THE TN VALLEY DURING THE OVERNIGHT PERIOD. AS THE SQUALL-LINE MOVES EWD ACROSS THE MODERATE RISK AREA...A WIDESPREAD SEVERE THREAT WILL EXIST AND SEVERAL SIGNIFICANT EVENTS APPEAR LIKELY. OBJECTIVE ANALYSIS CURRENTLY SHOWS A POCKET OF MODERATE INSTABILITY EXTENDING FROM NE TX NEWD INTO CNTRL AR WHERE THE LITTLE ROCK 00Z SOUNDING SHOWS MUCAPE AROUND 1100 J/KG. THIS INSTABILITY WAS CO-LOCATED WITH A POCKET OF MID 60S F SFC DEWPOINTS WHICH SHOULD CONTINUE TO ADVECT NEWD ACROSS THE MODERATE RISK AREA. THE LITTLE ROCK SOUNDING ALSO SHOWS 70 KT OF DEEP LAYER SHEAR WHICH COMBINED WITH THE INSTABILITY SHOULD EASILY SUPPORT SUPERCELL DEVELOPMENT. CURRENT RADAR TRENDS SHOW MULTIPLE DISCRETE CELLS DEVELOPING JUST TO THE WEST OF LITTLE ROCK. AS THESE CELLS MOVE ACROSS CNTRL AND ERN AR AND INTO THE CORE OF THE LOW-LEVEL JET...SHEAR WILL BE FAVORABLE FOR SUPERCELLS AND TORNADOES. AT LITTLE ROCK...0-3 KM STORM RELATIVE HELICITIES OF 500 TO 600 M2/S2 AND LCL HEIGHTS BELOW 700 METERS SHOULD BE SUFFICIENT FOR STRONG TORNADOES ESPECIALLY WITH DISCRETE CELLS THAT REMAIN AHEAD OF THE SQUALL-LINE. 50 TO 60 KT OF FLOW AT 1 TO 2 KM SHOULD ALSO MAKE CONDITIONS FAVORABLE FOR WIDESPREAD WIND DAMAGE AS THE SQUALL-LINE CONTINUES TO ORGANIZE. THE WIND DAMAGE AND TORNADO THREAT IS EXPECTED TO CONTINUE INTO WCNTRL TN...ECNTRL MS AND WRN AL AFTER MIDNIGHT WITH A SEVERE THREAT POSSIBLE THROUGH MUCH OF THE OVERNIGHT PERIOD. ...OH VALLEY... A SQUALL-LINE IS CURRENTLY ONGOING FROM ECNTRL IL SWWD ACROSS SE MO LOCATED IN THE EXIT REGION OF A PRONOUNCED 70 TO 80 KT MID-LEVEL JET. AS THIS JET EJECTS NEWD ACROSS THE OH VALLEY THIS EVENING...DEEP LAYER SHEAR WILL CONTINUE TO STRENGTHEN. THIS COMBINED WITH STRONG LARGE-SCALE ASCENT SHOULD ENABLE THE SQUALL-LINE TO ORGANIZE WITH THE LINE MOVING EWD ACROSS IND AND WRN KY LATE THIS EVENING. INCREASING LOW-LEVEL MOISTURE AND INSTABILITY COMBINED WITH VERY STRONG FLOW JUST ABOVE THE SFC...SHOULD ENABLE THE SQUALL-LINE TO BECOME AN EFFICIENT WIND DAMAGE PRODUCER. AS SFC DEWPOINTS GRADUALLY INCREASE INTO THE LOWER 60S F ACROSS PARTS OF THE OH VALLEY...A TORNADO THREAT WILL ALSO BE POSSIBLE ESPECIALLY WITH ROTATING CELLS EMBEDDED IN THE LINE. ..BROYLES.. 01/30/2013 CLICK TO GET WUUS01 PTSDY1 PRODUCT NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z