MESOSCALE DISCUSSION 1326
   NWS STORM PREDICTION CENTER NORMAN OK
   0650 PM CDT THU JUN 25 2009
   
   AREAS AFFECTED...SERN WY...NEB PANHANDLE...NERN CO
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 511...
   
   VALID 252350Z - 260045Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 511
   CONTINUES.
   
   AN ISOLATED THREAT FOR DAMAGING WINDS AND LARGE HAIL WILL EXIST
   DURING THE EVENING FOR LOCATIONS WITHIN AND E OF WW 511.
   HOWEVER...CURRENT CONVECTIVE TRENDS SUGGEST A REPLACEMENT OR
   EXTENSION OF WW 511 WILL NOT BE LIKELY. IN ADDITION TO THE MARGINAL
   SEVERE WEATHER THREAT...LOCALLY HEAVY RAIN MAY OCCUR WITH THE
   STRONGER THUNDERSTORM CORES.
   
   RECENT REGIONAL REFLECTIVITY IMAGERY CONTINUES TO SHOW NUMEROUS
   STORMS DRIFTING ENE ACROSS THE PLAINS OF ERN CO. A BROKEN LINE OF
   STORMS WAS ALSO LOCATED FROM 25 WNW OF TOR TO 35 E OF CDR. RADAR
   TRENDS SHOW MUCH OF THIS ACTIVITY QUICKLY PULSES UP IN
   INTENSITY...BUT THEN DIMINISHES IN STRENGTH AFTER ONE OR TWO
   ADDITIONAL VOLUME SCANS. THIS WEAK STORM INTENSITY MAY PARTIALLY BE
   A RESULT OF MARGINAL 0-6 KM MEAN FLOW. IN ADDITION...WIDESPREAD
   CONVECTIVE OVERTURNING IN CO IS RESULTING IN EXPANDING OUTFLOW/COLD
   POOLS AND STORM MERGERS...WHICH APPEARS TO BE INHIBITING MAINTENANCE
   OF STRONG PERSISTENT UPDRAFTS. AS THE LOW LEVEL JET STRENGTHENS
   DURING THE EVENING...A LOOSELY ORGANIZED MCS MAY DEVELOP OVER THE
   CENTRAL HIGH PLAINS...AND SPREAD E INTO PORTIONS OF WRN NEB AND KS.
   HOWEVER...THE SEVERE WEATHER THREAT APPEARS TO BE FAIRLY LOW...AND
   WW 511 WILL LIKELY BE ALLOWED TO EXPIRE AT 02Z. 
   
   IN ADDITION TO THE SEVERE WEATHER THREAT...SLOW MOVING THUNDERSTORMS
   OCCURRING WITHIN A WEAK SHEAR/FAVORABLY MOIST UPSLOPE FLOW
   ENVIRONMENT MAY PRODUCE RAINFALL RATES OF 1-2 IN/HR OVER PORTIONS OF
   NERN CO DURING THE NEXT SEVERAL HOURS. THIS THREAT WILL LIKELY SHIFT
   INTO PORTIONS OF THE SRN NEB PANHANDLE AS WELL AS WRN/SWRN NEB
   THROUGH THE EARLY NIGHT TIME HOURS.
   
   ..GARNER.. 06/25/2009
   
   
   ATTN...WFO...LBF...GLD...BOU...CYS...
   
   LAT...LON   42840550 42830269 39160250 39130509 42840550