MESOSCALE DISCUSSION 0024
   NWS STORM PREDICTION CENTER NORMAN OK
   0353 AM CST SUN JAN 13 2013
   
   AREAS AFFECTED...ERN TX...NRN LA...SE AR...WRN MS
   
   CONCERNING...TORNADO WATCH 4...
   
   VALID 130953Z - 131130Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 4 CONTINUES.
   
   SUMMARY...SEVERE WEATHER POTENTIAL APPEARS TO BE DIMINISHING.  THE
   REMAINING VALID PORTION OF WW 4 MAY BE CANCELLED EARLY.
   
   DISCUSSION...A SHARP SURFACE FRONTAL ZONE CONTINUES A SLOW SOUTHWARD
   ADVANCEMENT ACROSS THE LOWER MISSISSIPPI VALLEY/WESTERN GULF COAST
   REGION.  THE MOST SUBSTANTIVE RECENT NEW CONVECTIVE DEVELOPMENT HAS
   BEEN OCCURRING IN A POST-FRONTAL WARM ADVECTION REGIME ACROSS PARTS
   OF EASTERN TEXAS...WHERE A MOIST SOUTHERLY INFLOW OF GULF MOISTURE
   CONTINUES ABOVE A SHALLOW...BUT DEEPENING SURFACE BASED STABLE
   LAYER.  GIVEN CAPE EVIDENT IN RAPID REFRESH FORECAST
   SOUNDINGS...SOME HAIL MAY NOT BE COMPLETELY OUT OF THE QUESTION WITH
   THESE STORMS...BUT THIS POTENTIAL SEEMS LIKELY TO DIMINISH THROUGH
   11-12Z...AS THE COLD SURFACE-BASED LAYER CONTINUES TO DEEPEN ACROSS
   THE SABINE VALLEY AND TEXAS COASTAL PLAIN.  OTHERWISE...WITH THE
   MOST PROMINENT FRONTAL WAVE NOW DEVELOPING ACROSS THE UPPER OHIO
   VALLEY INTO THE LOWER GREAT LAKES REGION...POTENTIAL FOR STRONG
   BOUNDARY LAYER BASED STORM DEVELOPMENT ACROSS THE LOWER MISSISSIPPI
   VALLEY APPEARS LOW THROUGH AT LEAST MID TO LATE MORNING.
   
   ..KERR.. 01/13/2013
   
   
   ATTN...WFO...MEG...JAN...LZK...LCH...SHV...
   
   LAT...LON   31469404 32419347 33249260 34229167 34659134 34839101
               34818996 34688862 33638946 32269075 31239179 31469404