MESOSCALE DISCUSSION 1096
   NWS STORM PREDICTION CENTER NORMAN OK
   0253 PM CDT MON JUN 11 2007
   
   AREAS AFFECTED...SOUTHEAST MT/NORTHEAST WY INTO THE WESTERN DAKOTAS
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 111953Z - 112200Z
   
   SEVERE THUNDERSTORM THREAT IS EXPECTED TO INCREASE OVER THE NEXT FEW
   HOURS FROM SOUTHEAST MT/NORTHEAST WY INTO THE WESTERN DAKOTAS. A
   WATCH WILL LIKELY BE NEEDED BY 2030Z.
   
   LATEST SURFACE ANALYSIS FEATURES 1003 MB SURFACE LOW ACROSS
   NORTHWEST SD...WITH ASSOCIATED COLD FRONT EXTENDING ALONG THE MT/ND
   BORDER...ANGLING INTO NORTHEAST/CENTRAL WY. LEE TROUGH NOTED
   SOUTHWARD FROM THE SURFACE LOW INTO FAR EASTERN WY/FAR WESTERN NEB
   INTO NORTHEAST CO. GIVEN ADDITIONAL HEATING/LARGE SCALE ASCENT
   ASSOCIATED WITH WESTERN MT SHORTWAVE TROUGH...INCREASING
   THUNDERSTORM COVERAGE IS EXPECTED TO INITIALLY BE FOCUSED ON THESE
   AFOREMENTIONED FEATURES...AND OROGRAPHICALLY FAVORED AREAS SUCH AS
   THE BLACK HILLS/BIG HORN MOUNTAINS. STORMS HAVE ALREADY DEVELOPED
   ACROSS INTERIOR WY...AS WELL AS THE BLACK HILLS IN WESTERN SD WHERE
   A SPECIAL 19Z OBSERVED RAOB FROM RAPID CITY IS REFLECTIVE OF A VERY
   HOT/MIXED BOUNDARY LAYER.
   
   BENEATH A PLUME OF STEEP MID LEVEL LAPSE RATES...A RELATIVELY MOIST
   AIRMASS EXISTS ACROSS THE NORTHERN HIGH PLAINS...WITH LOWER TO
   MIDDLE 60S F DEWPOINTS RESIDING ACROSS MUCH OF THE WESTERN/CENTRAL
   DAKOTAS...WITH 50S F IN THE POST-FRONTAL REGIME ACROSS SOUTHEAST
   MT/NORTHEAST WY. THIS WILL CONTRIBUTE TO MLCAPE VALUES RANGING FROM
   1000-1500 J/KG ACROSS FAR SOUTHEAST MT/NORTHEAST WY TO GREATER THAN
   3000 J/KG ACROSS MUCH OF ND/NORTHERN SD. THE DEGREE OF INSTABILITY
   AND MODERATE SOUTHWESTERLY FLOW ALOFT WILL SUPPORT ROTATING
   STORMS/SUPERCELLS CAPABLE OF LARGE HAIL AND DAMAGING WIND GUSTS.
   
   ..GUYER.. 06/11/2007
   
   
   ATTN...WFO...ABR...BIS...UNR...BYZ...GGW...
   
   45460755 45870677 45950540 46940438 48770321 48840100
   48490025 46520023 44780046 43330140 43300317 43790397
   44060513 44580605 44700706