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

   SPC AC 171617
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1117 AM CDT MON MAR 17 2008
   
   VALID 171630Z - 181200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS LATER THIS AFTERNOON AND TONIGHT
   ACROSS PORTIONS OF NORTH AND CENTRAL TEXAS...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A LARGE PORTION OF
   SOUTHERN PLAINS TO LOWER  MO VALLEY...
   
   ,..SRN PLAINS...
   COLD UPPER LOW CONTINUES TO DEVELOP SEWD INTO NERN MEXICO WITH
   STRONG HEIGHT FALLS AND LARGE SCALE ASCENT SPREADING ACROSS LOWER
   RIO GRANDE VALLEY INTO SWRN TX LATER TONIGHT. WHILE ONE SPEED MAX
   NOW EXITING THE UPPER SYSTEM ACROSS CENTRAL PLAINS ATTM THE PRIMARY
   500MB 100KT WIND MAX WILL APPROACH S TX AFTER 06Z TONIGHT.
   
   COLD FRONT TRAILS FROM SERN KS TO SWRN OK THEN WWD INTO ERN NM. 
   FROM A WEAK LOW CENTER E OF LBB A DRY LINE EXTENDS SWD INTO MEX
   VICINITY RIO GRANDE BIG BEND.
   
   THE WARM SECTOR E OF DRY LINE IS CHARACTERIZED BY A RELATIVELY
   SHALLOW LAYER OF VERY MOIST GULF AIR WITH DEWPOINTS WELL INTO THE
   60S NWD TO RED RIVER BY THIS AFTERNOON. MOISTURE IS CAPPED BY A
   PRONOUNCED EML WHERE MID LEVEL LAPSE RATES ARE GENERALLY IN EXCESS
   OF 8C/KM.
   
   DAYTIME HEATING WILL WEAKEN CAP PARTICULARLY VICINITY DRY LINE AND
   NEAR COLD FRONT NWRN TX. WITH MLCAPES CLIMBING TO AT LEAST  2000
   J/KG AND THE PRESENCE OF STRONG DEEP LAYER SHEAR... THREAT FOR
   SURFACE INITIATION WILL INCREASE BY MID/LATE AFTERNOON VICINITY COLD
   FRONT AND DRY LINE . STORMS ABLE TO FORM WILL QUICKLY BECOME SEVERE
   WITH POTENTIAL FOR VERY LARGE HAIL AND TORNADOES.
   
   BY THIS EVENING THE DRY LINE WHICH WILL LIKELY MIX EWD THIS
   AFTERNOON INTO WCENTRAL TX WILL LIKELY RETREAT AHEAD OF STRONG
   ASCENT AND UPPER JET APPROACHING FROM NERN MEXICO.  EXACTLY WHERE
   THE DRY LINE WILL SET UP THIS EVENING IS A LITTLE
   UNCERTAIN...HOWEVER CONDITIONS ALONG AND TO THE E WILL BE VERY
   FAVORABLE FOR SUPERCELL DEVELOPMENT INCLUDING POTENTIAL FOR
   TORNADOES AND VERY LARGE HAIL.  THUS THE UPGRADE TO A MDT RISK FOR
   THE AREA OF GREATEST CONCERN FOR THE EARLY EVENING/OVERNIGHT
   DEVELOPMENT OF TORNADIC SUPERCELLS.  THERE IS THE POTENTIAL OF
   STRONG TORNADOES GIVEN THE STRENGTH OF THE BACKGROUND WIND FIELDS
   AND EXPECTED THERMODYNAMICS. SHEAR WILL BECOME VERY FAVORABLE AS LOW
   LEVEL JET IN S TX BACKS AND INCREASES TO 50KT ENHANCING THE
   POTENTIAL FOR SUPERCELLS.
   
   CONVECTION WILL LIKELY EVOLVE MORE INTO A LINEAR MODE LATER TONIGHT
   WITH AN INCREASING CONCERN FOR WIND DAMAGE EXTENDING EWD ACROSS
   CENTRAL TX.
   
   FURTHER N INTO OK AND LOWER MO VALLEY...MUCH OF THUNDERSTORMS WILL
   REMAIN ELEVATED THROUGH THE PERIOD WITH PRIMARILY A HAIL THREAT.  A
   LITTLE GREATER THREAT FOR SURFACE BASED STORMS INTO OK E OF COLD
   FRONT WHICH WOULD INCREASE POTENTIAL FOR SUPERCELLS INCLUDING
   ISOLATED TORNADOES AND LARGE HAIL LATER THIS AFTERNOON AND EVENING.
   
   ..HALES/HURLBUT.. 03/17/2008
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z