Mike Wilhelm's Alabama Weather Blog

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Bamawx.com

...WRN GULF COAST/LWR MS VALLEY INTO MID/SRN ATLANTIC SEABOARD...
  BOUNDARY LAYER MODIFICATION MAY BEGIN TO OCCUR IN THE WAKE OF THE
  RECENT COLD INTRUSION TO THE LEE OF THE CENTRAL/SOUTHERN
  APPALACHIANS.  BUT...THE REMNANTS OF ONGOING CONVECTION OVER THE
  OHIO VALLEY ARE EXPECTED TO SPREAD AHEAD OF THE COLD FRONT AND
  PROVIDE A STABILIZING INFLUENCE ACROSS THE MID ATLANTIC STATES
  TODAY.  MODELS ARE SUGGESTIVE THAT THE MOST SIGNIFICANT WARM SECTOR
  DESTABILIZATION WILL BECOME FOCUSED ACROSS PARTS OF THE LOWER
  MISSISSIPPI VALLEY/CENTRAL GULF STATES...WHERE HEATING OF A MOIST
  BOUNDARY LAYER COUPLED WITH MODEST LAPSE RATES MAY YIELD CAPE IN
  EXCESS OF 2000 J/KG.
 
  INSTABILITY IS EXPECTED TO CONTRIBUTE TO VIGOROUS NEW CONVECTIVE
  DEVELOPMENT...OR REINTENSIFICATION OF EARLY MORNING CONVECTIVE
  ACTIVITY...SUPPORTED BY FORCING ASSOCIATED WITH THE SOUTHERN BRANCH
  TROUGH...AS IT SPREADS INTO THE LOWER MISSISSIPPI VALLEY.  THIS
  COULD OCCUR AS EARLY AS 16-18Z...FROM PARTS OF EASTERN TEXAS INTO
  NORTHERN MISSISSIPPI.  AND...AS FORCING CONTINUES EASTWARD...THE
  EVOLUTION OF A QUASI-LINEAR MESOSCALE CONVECTIVE SYSTEM APPEARS
  POSSIBLE...PERHAPS PRECEDED BY A FEW MORE ISOLATED OR DISCRETE
  STORMS. 
 
  GIVEN THE MAGNITUDE OF THE ANTICIPATED INSTABILITY...MODERATE DEEP
  LAYER SHEAR...AND MOMENTUM ASSOCIATED WITH A 30-50 KT SOUTHWESTERLY
  PRE-FRONTAL 850 JET...SHOULD CONTRIBUTE TO THE POTENTIAL FOR
  DAMAGING WIND GUSTS...AND LARGE HAIL.  AND...LOW- LEVEL SHEAR WILL
  BE FAVORABLE FOR TORNADIC DEVELOPMENT... PARTICULARLY IN ANY
  SUSTAINED DISCRETE STORMS.
 
  A SEVERE THREAT IS EXPECTED TO PERSIST WITH ACTIVITY INTO EARLY
  EVENING AS IT SPREADS THROUGH MUCH OF THE REMAINDER OF CENTRAL/
  SOUTHERN MISSISSIPPI AND ALABAMA.  BUT...THIS THREAT IS EXPECTED TO
  WANE IN A MORE STABLE/STABILIZING ENVIRONMENT ACROSS THE EASTERN
  GULF/SOUTH ATLANTIC COAST STATES DURING THE LATE EVENING/OVERNIGHT
  HOURS.