MESOSCALE DISCUSSION 1662
   NWS STORM PREDICTION CENTER NORMAN OK
   0537 PM CDT FRI JUL 24 2009
   
   AREAS AFFECTED...S-CNTRL AND SERN NEB
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 242237Z - 242330Z
   
   CONVECTIVE INITIATION IS BEING CLOSELY MONITORED DUE TO THE
   POSSIBILITY OF ISOLD SEVERE STORM DEVELOPMENT...MAINLY ACROSS PARTS
   OF PARTS OF THE I-80 CORRIDOR IN CNTRL AND ERN NEB.
   
   RECENT LOOPS IN VISIBLE IMAGERY AND SINGLE SITE RADAR DATA INDICATE
   THE REMAINING CAP HAS WEAKENED CONSIDERABLY THE PAST FEW HOURS ALONG
   THE SWD SAGGING FRONTAL BOUNDARY--EVIDENT BY GROWING TCU FIELD. 
   THIS BOUNDARY AS OF 2230Z IS LOCATED FROM NEAR LBF ENEWD TO 10 MI N
   TQE WHERE LOW LEVEL CONVERGENCE IS MAXIMIZED.  THE AIRMASS HAS
   BECOME QUITE HOT WITH TEMPS RANGING FROM THE LOWER TO UPPER 90S AND
   DEWPOINTS GENERALLY HOLDING INTO THE UPPER 60S.  MODIFIED RUC
   FORECAST SOUNDINGS SUGGEST LITTLE IN THE WAY OF REMAINING CINH USING
   A MIXED LAYER PARCEL AND MLCAPE EXCEEDING 3000 J/KG.  ONE LIMITING
   FACTOR THAT WILL TEND TO SUPPRESS CONVECTIVE INITIATION IS NEUTRAL
   OR WEAK SHORTWAVE RIDGING OCCURRING OVER THE DISCUSSION AREA.  
   
   NONETHELESS...CURRENT THINKING IS SUSTAINED MASS CONVERGENCE INVOF
   OF THE FRONTAL WITHIN DEEPENING TCU FIELD MAY LEAD TO THE BREACHING
   OF THE CAP WITHIN THE NEXT HOUR OR SO.  ONCE THIS OCCURS...MORE THAN
   ADEQUATE DEEP LAYER SHEAR PROFILE ACCORDING TO FBY VWP /40 KTS 0-6
   KM SHEAR/ IS SUPERCELL-SUPPORTIVE WITHIN THIS STRONGLY UNSTABLE
   ENVIRONMENT.  ASSUMING ISOLD STORMS DEVELOP AND BECOME
   SUSTAINED/ORGANIZE...THE POSSIBILITY OF LARGE TO VERY LARGE HAIL
   WILL INCREASE.
   
   ..SMITH.. 07/24/2009
   
   
   ATTN...WFO...OAX...GID...LBF...
   
   LAT...LON   40039712 40069948 40389978 41019991 41179977 41689739
               41579703 40909654 40189659 40039712