MESOSCALE DISCUSSION 1125
   NWS STORM PREDICTION CENTER NORMAN OK
   0352 PM CDT MON MAY 26 2003
   
   AREAS AFFECTED...ERN MT/ERN WY/FAR WRN SD
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 262052Z - 262215Z
   
   THUNDERSTORMS WILL CONTINUE TO DEVELOP DURING THE NEXT FEW HOURS
   ACROSS ERN WY NWD INTO ERN MT...WITH A THREAT FOR LARGE HAIL/
   DAMAGING WINDS.  WW NOT ANTICIPATED ATTM...BUT MAY BE REQUIRED LATER
   THIS AFTERNOON/EARLY EVENING IF ACTIVITY BECOMES MORE NUMEROUS.
   
   20Z SURFACE ANALYSIS SHOWS A BOUNDARY EXTENDING FROM NERN MT NEAR
   OLF SWWD TO AROUND LVM...WITH A LEE TROUGH EXTENDING FROM SOUTH-
   CENTRAL/SERN MT SWD TO NERN CO.  VIS IMAGERY/LIGHTNING DATA SHOW
   STORMS CONTINUING TO DEVELOP OVER THE HIGHER TERRAIN OF ERN WY/FAR
   WRN SD INTO SOUTH CENTRAL MT.  AIR MASS OVER ERN MT/ERN WY INTO FAR
   WRN SD HAS BECOME MODERATELY UNSTABLE...WITH OBJECTIVE ANALYSES
   SHOWING DEEP LAYER SHEAR BECOMING MORE FAVORABLE FOR ORGANIZED
   STORMS.  
   
   SUPERCELLS WILL BE MOST LIKELY OVER ERN MT...WHERE STRONGER DEEP
   LAYER SHEAR IS EXPECTED.  FURTHER SOUTH...STORMS OVER ERN WY SHOULD
   HAVE A DIFFICULT TIME MOVING EWD OFF THE HIGHER TERRAIN INTO THE
   AXIS OF GREATER INSTABILITY...GIVEN VERY SLOW STORM MOTIONS.
   
   ..PETERS.. 05/26/2003
   
   
   ATTN...WFO...UNR...CYS...GGW...BYZ...RIW...
   
   45020715 47040718 47560418 43780394 41240412 41330559