Categorical Graphic
Probabilistic Tornado Graphic
Probabilistic Damaging Wind Graphic
Probabilistic Large Hail Graphic

   SPC AC 161243
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0643 AM CST SAT FEB 16 2008
   
   VALID 161300Z - 171200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF ERN/SRN TX AND
   WRN/SRN LA...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM CNTRL TX INTO THE LWR MS
   VLY...
   
   ...SYNOPSIS...
   UPPER LOW NOW NEAR ELP WILL CONTINUE E/ENE ACROSS THE REMAINDER OF
   WEST TX TODAY...BEFORE ACCELERATING NE TOWARD THE MO OZARKS
   TONIGHT/EARLY SUNDAY.  AT THE SFC...LOOSELY-CONSOLIDATED LOW NOW
   FORMING ALONG STALLED FRONT IN S CNTRL TX EXPECTED TO STRENGTHEN AND
   DEVELOP NNE ALONG THE BOUNDARY THROUGH THE DAY.  THE LOW SHOULD
   REACH THE PRX AREA BY EVENING AS DIFFUSE MARITIME WARM FRONT...NOW
   EXTENDING NW/SE ACROSS SE TX...LIFTS N INTO CNTRL LA.  THE LOW
   SHOULD CONTINUE NNE INTO CNTRL MO BY 12Z SUNDAY AS INCREASING WLY
   FLOW S OF LOW ACCELERATES ITS TRAILING COLD FRONT E/SE INTO WRN
   TN/CNTRL MS AND SE LA.
   
   ...ERN/SRN TX INTO WRN/SRN LA...
   SEASONABLY WARM AND VERY HUMID AIR WILL BE PRESENT TODAY E OF SFC
   FRONT NOW STALLING ALONG A NNE/SSW AXIS E OF THE I-35 CORRIDOR OVER
   SRN AND ERN TX.  THIS RICH BOUNDARY LAYER AIR WILL EXTEND NE TO
   VICINITY OF DIFFUSE WARM FRONT NOW NEAR CLL/BPT.
   
   SHORTWAVE RIDGING AND EXISTING EML DOWNSTREAM FROM APPROACHING UPR
   LOW LIKELY WILL KEEP MOST OF REGION CAPPED TO DEEP CONVECTIVE
   DEVELOPMENT THROUGH MUCH OF THE DAY.  WITH TIME...HOWEVER...
   COMBINATION OF SFC HEATING AND INCREASING LARGE SCALE ASCENT
   EXPECTED TO SUPPORT TSTM DEVELOPMENT ALONG AND POSSIBLY IMMEDIATELY
   AHEAD OF NNE/SSW FRONT AS THAT BOUNDARY BEGINS TO ACCELERATE E AS A
   COLD FRONT...AND SBCAPE INCREASES TO AROUND 1500 J/KG.
   
   WITH 500 MB SSW FLOW INCREASING TO AOA 60 KTS AND 50 KT SLY FLOW
   PERSISTING JUST ABOVE THE SFC...SETUP WILL BE FAVORABLE FOR
   DEVELOPMENT OF BACK-BUILDING BANDS OF SUPERCELLS THAT SHOULD FAIRLY
   QUICKLY MERGE INTO AN EXTENSIVE SQLN.  EMBEDDED STORMS WITHIN THESE
   BANDS COULD YIELD A FEW STRONG TORNADOES...IN ADDITION TO
   DESTRUCTIVE OUTFLOW WINDS...GIVEN LONG/HOOKED HODOGRAPHS WITH 0-1 KM
   SRH AROUND 350 M2/S2.  LARGE HAIL MAY ALSO OCCUR...ESPECIALLY ON SRN
   END OF SQLN IN S CNTRL TX...WHERE SBCAPE SHOULD EXCEED 2000 J/KG.  A
   SIGNIFICANT TORNADO THREAT WOULD ALSO EXIST WITH ANY DISCRETE STORMS
   THAT FORM IN AREA OF WEAKENING CIN IMMEDIATELY AHEAD OF SQLN.
   
   WITH THE LOW LEVEL MOISTURE RETURN LIKELY TO CONTINUE AHEAD OF THE
   SQLN DURING THE OVERNIGHT ACROSS LA...THE THREAT FOR HIGH WIND AND
   ISOLATED STRONG TORNADOES COULD CONTINUE THROUGH EARLY
   SUNDAY...ESPECIALLY OVER WRN AND SRN LA.
   
   ...W CNTRL/NW TX...
   SCTD ELEVATED TSTMS EXPECTED TO PERSIST FROM NW TO S CNTRL TX
   THROUGH ABOUT MID AFTN IN AREA OF WAA/ASCENT ON WRN EDGE OF
   STRENGTHENING SLY LLJ.  SUFFICIENT MUCAPE /AOA 500 J PER KG/ SHOULD
   REMAIN PRESENT TO SUPPORT A CONTINUED THREAT FOR ISOLATED
   HAIL...UNTIL MORE NEARLY SFC-BASED STORMS INCREASE IN
   COVERAGE/STRENGTH FARTHER TO THE E A BIT LATER IN THE DAY. 
   STRONG...UNIDIRECTIONAL SLY CLOUD-LAYER FLOW SHOULD ORGANIZE THE
   STORMS INTO N-S BACK-BUILDING BANDS.  THESE STRUCTURES COULD YIELD A
   FEW CORRIDORS OF HEAVY RAIN IN AREAS AT OR CLOSE TO FREEZING.
   
   ...NE TX INTO SE OK/AR...
   STORMS IN NRN SEGMENT OF FRONTAL SQLN...N OF DIFFUSE MARITIME
   FRONT...COULD YIELD LARGE HAIL AND STG GUSTS AS THEY MOVE NNE WITHIN
   SLIGHTLY ELEVATED PLUME OF FAVORABLE BUOYANCY/MOISTURE OVER SE
   OK...SRN/CNTRL AR...NRN LA AND EXTREME NE TX.  ALTHOUGH LAPSE RATES
   ALOFT MAY BE WEAKER THAN FARTHER SW...RICH MOISTURE SHOULD
   SUPPORT MUCAPE UP TO 1000 J/KG...WITH 45-55 KT CLOUD-LAYER SHEAR AS
   EJECTING UPR SYSTEM ASSUMES AN INCREASINGLY NEGATIVE TILT.
   
   ...LA/WRN MS THIS MORNING...
   A FEW SLIGHTLY ELEVATED SUSTAINED STORMS/SUPERCELLS MAY PERSIST
   THROUGH THIS MORNING OVER CNTRL/NRN LA AND SW MS...IN WAA ZONE NE OF
   MARITIME FRONT.  THIS ACTIVITY MAY POSE A THREAT FOR LOCALLY
   DAMAGING WIND BUT SHOULD GRADUALLY WEAKEN AND SHIFT NWD AS HEIGHTS
   CONTINUE TO RISE DOWNSTREAM FROM APPROACHING UPR LOW.  SEE UPCOMING
   MCD FOR MORE DETAILS.
   
   ..CORFIDI.. 02/16/2008
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z