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

   SPC AC 091635
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   ISSUED BY AFWA OFFUTT AIR FORCE BASE BELLEVUE NE
   1035 AM CST THU MAR 09 2006
   
   VALID 091630Z - 101200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS LOWER MISSISSIPPI VALLEY THROUGH
   MIDDLE TENNESSEE VALLEY...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS CENTRAL GULF COAST STATES INTO
   THE OH RIVER VALLEY...
   
   ...SYNOPSIS...
   MORNING MODELS AND ONGOING OBSERVATIONAL TRENDS SUGGEST LITTLE
   CHANGE NEEDED TO ONGOING OUTLOOK/SCENARIO ATTM.  STRONG MID/UPPER
   SYSTEM EJECTING AS A FAST-MOVING...NEGATIVELY-TILTED SHORTWAVE
   TROUGH ACROSS THE MID SOUTH TODAY AND INTO THE LOWER GREAT LAKES BY
   THE END OF THE PERIOD. SUBSTANTIAL MID LEVEL JET MAX WITH H5 WINDS
   IN EXCESS OF 80 KT WILL PROGRESS EWD ACROSS A LARGE PORTION OF THE
   LOWER/MID MS AND TN RIVER VALLEYS.
   
   ...LOWER OH RIVER VALLEY INTO LOWER/MID MS AND TN RIVER VALLEYS...
   ONGOING CONVECTION THIS MORNING WILL CONTINUE TO MOVE EASTWARD THIS
   MORNING WITH DRY SLOT ALREADY SPREADING THROUGH EASTERN TX AND
   WESTERN AR.  SUFFICIENT MOMENTUM MIXING DOWN TO THE SURFACE BEHIND
   THUNDERSTORM LINES...MARGINAL INSTABILITY AHEAD OF SYSTEM...AND
   STRONG SHEAR WILL COMBINE TO PRODUCE MULTIPLE LINES OF THUNDERSTORMS
   WITH A FEW DISCRETE CELLS AHEAD OF AND EMBEDDED WITHIN THE LINES. 
   SHEAR IS QUITE IMPRESSIVE OVER MOST OF THE REGION WITH AREA VWP/S
   AND PROFILERS INDICATING 0-1/0-2 KM SRH IN EXCESS OF 300 M2/S2 AND
   SFC-6 KM SHEAR EXCEEDING 80 KT.
   
   LIMITING FACTOR ATTM IS LACK OF SIGNIFICANT INSTABILITY AHEAD OF
   LINE.  SURFACE DEW POINTS IN THE LOW 60S WITH SURFACE TEMPERATURES
   IN THE LOW 70S WILL PROVIDE ENOUGH INSTABILITY FOR A FEW DISCRETE
   CELLS AND A POTENTIAL FOR ISOLATED STRONG TORNADOES AHEAD AND/OR
   EMBEDDED WITHIN THE SQUALL LINE...HOWEVER DONT EXPECT THIS TO BE
   WIDESPREAD.  STRONG FORCING AND STRENGTH OF LOW LEVEL SHEAR SUGGEST
   MULTIPLE LINES OF THUNDERSTORMS WITH SIGNIFICANT WIND DAMAGE DUE TO
   UPPER LEVEL MOMENTUM MIXING DOWN TO THE SURFACE COMBINED WITH QUICK
   MOVING STORMS.
   
   AS THE MAIN TROUGH LIFTS NEWD INTO THE OH VALLEY TONIGHT...THE
   STRONGER FORCING WILL BECOME MORE REMOVED FROM THE INSTABILITY.
   STORMS WITH MAINLY A WIND THREAT WILL SPREAD EWD INTO ERN KY SWD
   INTO WRN GA...THOUGH THE SEVERE THREAT SHOULD GRADUALLY DIMINISH
   THROUGH THE NIGHTTIME HOURS.
   
   ...LOWER OH/MID MS RIVER VALLEYS INTO THE LOWER GREAT LAKES...
   ISOLATED LARGE HAIL AND POSSIBLY DAMAGING WINDS WILL ACCOMPANY
   MORNING STORMS CURRENTLY OVERSPREADING COOL BOUNDARY LAYER NORTH OF
   EFFECTIVE WARM FRONT/OUTFLOW BOUNDARY EXTENDING FROM WRN KY INTO
   CENTRAL AR.  HOWEVER AS LOW CENTER DEEPENS ACROSS THE MID MS RIVER
   VALLEY...INSTABILITY AND SUBSEQUENT THUNDERSTORMS MAY BECOME MORE
   SURFACE BASED WITH DAMAGING WINDS AND POSSIBLY TORNADOES AS SHEAR
   REMAINS SUPPORTIVE OF SUPERCELLS AND SMALL LINES.
   
   ..AFWA.. 03/09/2006
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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