Categorical Graphic
Probabilistic Tornado Graphic
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
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
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 151927
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0127 PM CST WED FEB 15 2012
   
   VALID 152000Z - 161200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX INTO SW MS...
   
   EARLIER THOUGHTS REGARDING THE POTENTIAL FOR SEVERE THUNDERSTORMS
   ACROSS THE WRN/CNTRL GULF STATES PRIMARILY REMAIN.  OVER THE LAST
   FEW HOURS IT HAS BECOME MORE OBVIOUS THAT THE MCS OVER SERN TX WILL
   CONTINUE TO EXPAND IN AREAL COVERAGE AS IT SPREADS ACROSS THE SABINE
   RIVER INTO LA.  DESPITE THE WEAK INSTABILITY OBSERVED DOWNSTREAM IT
   APPEARS WARM ADVECTION ATOP THE RETREATING CONTINENTAL AIRMASS WILL
   PROVIDE ASCENT NECESSARY FOR CONVECTIVE GROWTH OVER THE LOWER MS
   VALLEY.  WHILE HAIL MAY AT TIMES BE NOTED ACROSS THE SRN/WRN FLANK
   WHERE LAPSE RATES ARE SOMEWHAT STEEPER...ISOLATED SEVERE WIND GUSTS
   MAY ULTIMATELY BE THE PRIMARY SEVERE THREAT WITH THIS COMPLEX OF
   STORMS AS IT SPREADS INTO LA.
   
   ..DARROW.. 02/15/2012
   
   .PREV DISCUSSION... /ISSUED 1030 AM CST WED FEB 15 2012/
   
   ...SYNOPSIS...
   A MIDLEVEL SHORTWAVE TROUGH WILL EJECT ENEWD FROM THE TX PANHANDLE
   TO THE I-35 CORRIDOR IN KS/NRN OK BY THIS EVENING...AND THEN
   CONTINUE TO THE LOWER OH VALLEY OVERNIGHT.  A REMNANT LEE CYCLONE
   NEAR THE NW OK/KS BORDER AS OF 16Z WILL LIKEWISE MOVE ENEWD TOWARD
   THE LOWER OH VALLEY...THOUGH IT APPEARS THAT THE LOW WILL SLOWLY
   WEAKEN AS THE MIDLEVEL TROUGH LOSES AMPLITUDE.  OTHERWISE...A
   MIDLEVEL LOW OVER W CENTRAL NV WILL PROGRESS SWD TO SRN CA WITH A
   MARGINAL RISK FOR THUNDERSTORMS INVOF SRN NV/SRN CA BY AFTERNOON.
   
   ...SE TX/CENTRAL LA THROUGH THIS EVENING...
   THE MIDLEVEL TROUGH AND ASSOCIATED HEIGHT FALLS WILL PASS WELL TO
   THE NW OF THIS AREA...AS A BELT OF 25-35 KT SWLY LOW-LEVEL FLOW
   DEVELOPS EWD/NEWD FROM AN E TX-AR AXIS THIS MORNING TO THE MS VALLEY
   THIS EVENING...AND THE TN/OH VALLEYS OVERNIGHT.  MEANWHILE...THE
   RICHEST LOW-LEVEL MOISTURE NOW ACROSS THE TX COASTAL PLAIN /BOUNDARY
   LAYER DEWPOINTS OF 65-70 F/ WILL SPREAD NEWD ACROSS SE TX TO SW LA
   THROUGH THIS EVENING.  BOTH THE 12Z CRP AND A SPECIAL 15Z SOUNDING
   FROM CLL REVEAL A CAP NEAR 800 MB...WITH STEEP LAPSE RATES IN THE
   800-600 MB LAYER.  CONTINUED MOISTENING WILL BOOST MLCAPE TO THE
   1000-1500 J/KG RANGE THIS AFTERNOON FROM THE MIDDLE TX COASTAL PLAIN
   INTO SE TX /ALONG AND S OF THE MARINE WARM FRONT/.
   
   WIDESPREAD CLOUDS WILL TEND TO LIMIT DAYTIME HEATING...BUT IT IS
   CLEAR THAT ASCENT IS ONGOING ALONG THE CORRIDOR FROM VCT TO CLL
   WHERE A POSSIBLE GRAVITY WAVE IS INTERACTING WITH THE WARM FRONT AND
   MOIST AXIS.  THE NEWLY DEVELOPED STORMS FROM VCT-CLL WILL LIKELY
   EVOLVE INTO MORE SURFACE-BASED CONVECTION BY EARLY AFTERNOON AND
   SPREAD ENEWD TOWARD THE TOLEDO BEND AREA LATER THIS AFTERNOON.  THE
   MODERATE INSTABILITY AND DEEP-LAYER VERTICAL SHEAR WILL SUPPORT A
   RISK FOR EMBEDDED SUPERCELLS WITH AN ASSOCIATED RISK FOR DAMAGING
   WINDS AND LARGE HAIL.  THERE WILL ALSO BE SOME RISK FOR A TORNADO OR
   TWO GIVEN EFFECTIVE SRH NEAR 150 M2/S2 AND A MOIST LOW-LEVEL
   ENVIRONMENT.  LATER THIS EVENING INTO TONIGHT...THE SEVERE STORM
   RISK WILL GRADUALLY DIMINISH AS THE MIDLEVEL WAVE EXITS TO NE AND
   ANY REMAINING ASCENT SPREADS NE OF THE SURFACE WARM SECTOR.
   
   ...N/NE OK/SE KS LATE THIS AFTERNOON...
   A NARROW UNSTABLE WARM SECTOR MAY DEVELOP IMMEDIATELY IN ADVANCE OF
   THE SURFACE LOW AND MIDLEVEL TROUGH CROSSING NRN OK/SRN KS THIS
   AFTERNOON/EVENING.  INSTABILITY MAY BECOME SUFFICIENT FOR LOW-TOPPED
   STORMS WITH A MARGINAL HAIL RISK.
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z