The first substantial severe weather outbreak of 2011 will be unfolding across Texas, Arkansas, Tennessee, Mississippi and Northern Alabama from today into the overnight of Thursday. Flooding rains in Kentucky and Tennessee may bring 2-4" of rain in addition to the tornadic threat that will increase throughout the afternoon.
With a strong low level jet aligning perpendicularly to the surface winds pushing warm in from the gulf, tornadic threat over eastern AR and Northern MS will provide ample shear for tornadic threat, with a high likelyhood of damaging hail as well.
The front will approach the will approach the Wiregrass by Friday Morning and is expected to weaking substantially, eliminating the threat for local severe weather.
DAY 1 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   0658 AM CST THU FEB 24 2011
  
   VALID 241300Z - 251200Z
  
   ...THERE IS A MDT RISK OF SVR TSTMS OVER PARTS OF THE LWR MS AND LWR
   TN VLYS...
  
   ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK
   AREA...FROM THE SRN PLNS ENE INTO THE LWR OH VLY...
  
   ...SYNOPSIS...
   POTENT SHORTWAVE TROUGH NOW OVER ERN NM EXPECTED TO CONTINUE ENE
   INTO ERN OK BY EVE AND INTO THE MID OH VLY BY 12Z FRI.  AT THE
   SFC...LOW NOW EVOLVING IN NW TX/SW OK SHOULD STRENGTHEN AND
   ACCELERATE ENE INTO N CNTRL AR BY EVE...BEFORE UNDERGOING MORE
   SUBSTANTIAL DEEPENING AND REACHING NRN WV EARLY FRI.  PACIFIC COLD
   FRONT NOW EMERGING OVER W TX SHOULD CONTINUE STEADILY E ACROSS TX
   AND SRN OK.  THE FRONT SHOULD OVERTAKE AN AXIS OF PRE-FRONTAL
   CONFLUENCE EXPECTED TO EVOLVE OVER E TX AND THE ARKLATEX LATER
   TODAY...AND CONTINUE E TO THE WRN SLOPES OF THE SRN/CNTRL
   APPALACHIANS BY 12Z FRI.
  
   COMBINATION OF STRENGTHENING WIND FIELD AND ASCENT WITH PROGRESSIVE
   UPR IMPULSE...CONTINUED MOISTURE INFLOW /WITH PW INCREASING TO AOA
   1.50 INCHES/...AND DIURNAL HEATING EXPECTED TO SUPPORT AN OUTBREAK
   OF SVR TSTMS OVER PARTS OF AR/TN AND ADJACENT STATES LATER TODAY
   INTO TONIGHT.
  
   ...SRN PLNS ENE INTO THE LWR TN VLY/LWR OH VLYS...
   STRENGTHENING SSWLY LOW-LVL FLOW IN WARM SECTOR OF DEEPENING SFC LOW
   WILL TRANSPORT SUBSTANTIAL MOISTURE NWD AND EWD INTO THE LWR MS AND
   TN VLYS LATER TODAY...AND INTO THE LWR/MID OH VLY BY TONIGHT...WITH
   PW VALUES LOCALLY EXCEEDING 1.75 INCHES.  COUPLED WITH POCKETS OF
   MODERATE SFC HEATING...SUFFICIENT INSTABILITY SHOULD DEVELOP TO
   SUPPORT NUMEROUS BANDS/CLUSTERS OF TSTMS AS 90-120 METER MID-LVL
   HEIGHT FALLS WITH UPR IMPULSE SWEEP ENEWD.
  
   TSTMS NOW OVER NW TX AND SW THROUGH NE OK SHOULD INCREASE COVERAGE
   AND POSSIBLY STRENGTH THROUGH MIDDAY AS LARGE SCALE ASCENT CONTINUES
   ENE INTO MOISTURE-RICH ENVIRONMENT.  RELATIVELY STEEP MID-LVL LAPSE
   RATES AND SIZABLE CLOUD-LAYER SHEAR SUGGEST POTENTIAL FOR HAIL AND
   POSSIBLY SHORT-LIVED BOWING SEGMENTS WITH HIGH WIND AS THE STORMS
   MOVE/DEVELOP MAINLY ENEWD.
  
   ADDITIONAL TSTMS EXPECTED TO FORM TOWARD MIDDAY OR BY EARLY AFTN
   ALONG CONFLUENCE AXIS FROM ERN OK/WRN AR SSW THROUGH THE ARKLATEX
   INTO E TX.  A FEW STORMS ALSO MAY FORM NEAR INTENSIFYING WARM FRONT
   EXTENDING ENE FROM THE AR SFC LOW INTO WRN/MIDDLE TN.  BOTH THE
   CONFLUENCE AXIS STORMS AND THOSE ALONG THE WARM FRONT WILL HAVE
   ACCESS TO THE RICHEST MOISTURE INFLOW AND MAXIMUM SFC HEATING OF THE
   PERIOD...WITH POCKETS OF SBCAPE EXPECTED TO BE AOA 1250 J PER KG.
   IN ADDITION...LOW- TO MID-LVL SHEAR WILL INCREASE SUBSTANTIALLY BY
   LATE IN THE DAY AS CORE OF 50+ KT 700 MB SW FLOW ASSOCIATED WITH NM
   UPR IMPULSE OVERSPREADS REGION.  THUS...THE AR AREA STORMS WILL POSE
   A THREAT FOR HIGH-IMPACT SVR WEATHER INCLUDING SUPERCELLS WITH
   BOWING SEGMENTS/HIGH WINDS...LARGE HAIL...AND POSSIBLY STRONG
   TORNADOES.  THE TORNADO THREAT WOULD APPEAR TO BE GREATEST FROM LATE
   THIS AFTN THROUGH EARLY TONIGHT NEAR WARM FRONT OVER CNTRL/NERN AR
   AND WRN/MIDDLE TN...WHERE 200-300 M2/S2 0-1KM SRH WILL EXIST INVOF
   DEEPENING SFC LOW.
  
   THE STORMS SHOULD EVOLVE INTO AN EXTENSIVE QLCS BY MID-EVE...WITH
   OVERALL LINE MOVEMENT TO THE ENE ACROSS TN/LWR OH VLYS...AND
   DEVELOPMENT SWD INTO LA/MS/AL THROUGH THE OVERNIGHT.  A CONTINUING
   THREAT DMGG WIND AND ISOLD TORNADOES LIKELY WILL PERSIST WELL INTO
   THE NIGHT...ESPECIALLY NEAR TRACK OF SFC LOW ...AND FARTHER S IN
   AREA OF GREATER SFC-BASED BUOYANCY IN MIDDLE TN...MS...AND NRN/WRN
   AL.
  
   ..CORFIDI/GARNER.. 02/24/2011
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