Apr 24, 2014 0600 UTC Day 1 Convective Outlook

DAY 1 CONVECTIVE OUTLOOK  

   NWS STORM PREDICTION CENTER NORMAN OK
   1256 AM CDT THU APR 24 2014

   VALID 241200Z - 251200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE
   LOWER-MIDDLE MS VALLEYS AND WRN TN VALLEY...

   ...SUMMARY...
   SCATTERED STRONG TO SEVERE STORMS ARE EXPECTED TO FORM ALONG A
   CORRIDOR FROM SOUTHEAST MISSOURI THROUGH ARKANSAS INTO NORTHERN
   LOUISIANA THURSDAY AFTERNOON...AND THEN SPREAD INTO WESTERN
   TENNESSEE AND NORTHWEST MISSISSIPPI THURSDAY EVENING.  LOCALLY
   DAMAGING WINDS AND LARGE HAIL WILL BE THE PRIMARY THREATS.

   ...SYNOPSIS...

   A PROGRESSIVE LOW-AMPLITUDE SYNOPTIC UPPER PATTERN WILL PERSIST
   THURSDAY. OF PARTICULAR INTEREST IS A VORTICITY MAXIMUM OVER NM 
   EMBEDDED WITHIN THE BASE OF AN UPPER TROUGH. THIS FEATURE WILL MOVE
   EAST INTO THE LOW-MIDDLE MS VALLEY THURSDAY AFTERNOON...THEN INTO
   THE TN AND OH VALLEYS DURING THE EVENING AND OVERNIGHT. THE
   ATTENDANT SFC LOW WILL DEVELOP NEWD THROUGH MO...IL AND
   INDIANA...WHILE TRAILING COLD FRONT ADVANCES SEWD THROUGH THE MIDDLE
   AND LOWER MS VALLEYS AND TX. BY 12Z FRIDAY THE FRONT WILL EXTEND
   FROM A SFC LOW OVER THE OH VALLEY SWWD THROUGH MIDDLE TN...SRN LA
   AND S TX.

   ...LOWER TO MIDDLE MS VALLEY AND WRN TN VALLEY AREAS...

   MOIST AXIS WITH UPPER 50S TO NEAR 60F BOUNDARY-LAYER DEWPOINTS WILL
   ADVECT INTO THE LOWER-MID MS VALLEY WARM SECTOR IN ASSOCIATION WITH
   MIGRATORY 30-40 KT SSWLY LLJ. MEANWHILE...STEEP 7-8 C/KM MID-LEVEL
   LAPSE RATES WILL SPREAD EWD ABOVE THE MOIST AXIS. AS TEMPERATURES
   WARM TO NEAR 80F...MLCAPE SHOULD INCREASE TO 1000-1500 J/KG FROM
   NERN TX INTO THE LOWER-MID MS VALLEY REGIONS. A CORRIDOR OF FOCUSED
   DEEP-LAYER ASCENT WILL SHIFT EWD THROUGH MO AND ARKANSAS ALONG AND
   JUST AHEAD OF THE COLD FRONT IN ASSOCIATION WITH THE PROGRESSIVE
   SHORTWAVE TROUGH. AS THIS ZONE OF ASCENT INTERACTS WITH THE
   DESTABILIZING BOUNDARY LAYER...STORMS ARE EXPECTED TO DEVELOP OVER
   MO...ARKANSAS AND POSSIBLY NERN TX AND LA DURING THE AFTERNOON AND
   SPREAD EWD TOWARD THE TN VALLEY REGION. 

   DEEP-LAYER WIND AND SHEAR PROFILES WILL STRENGTHEN IN VICINITY OF
   THE DEVELOPING CONVECTION AS A 50 KT MID-LEVEL JET WITHIN BASE OF
   UPPER TROUGH OVERTAKES THE COLD FRONT. EFFECTIVE BULK SHEAR
   INCREASING TO AOA 40 KT WILL SUPPORT ORGANIZED STORMS INCLUDING A
   FEW SUPERCELLS...BUT ACTIVITY MAY EVENTUALLY GROW UPSCALE INTO A
   DOMINANT LINEAR MODE WITH EMBEDDED ORGANIZED STRUCTURES AND CONTINUE
   EWD INTO THE TN VALLEY REGION. LARGE HAIL AND DAMAGING WIND GUSTS
   WILL BE THE INITIAL PRIMARY THREATS...BUT A COUPLE OF TORNADOES WILL
   ALSO BE POSSIBLE. DOMINANT THREAT IS EXPECTED TO TRANSITION TO
   DAMAGING WIND DURING THE EVENING BEFORE DIMINISHING LATER THURSDAY
   NIGHT.