MESOSCALE DISCUSSION 0797
   NWS STORM PREDICTION CENTER NORMAN OK
   0327 PM CDT MON MAY 11 2009
   
   AREAS AFFECTED...PORTIONS OF ERN AND CENTRAL ND
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 112027Z - 112130Z
   
   AN ISOLATED LARGE HAIL THREAT IS POSSIBLE OVER PORTIONS OF ERN AND
   CENTRAL ND. A WW IS NOT EXPECTED AT THIS TIME.
   
   OBSERVED SURFACE DATA INDICATE SSW WINDS OVER S CENTRAL-SERN ND
   BACKING TO SELY INVOF DVL...INDICATING THE PRESENCE OF A POSSIBLE
   OUTFLOW BOUNDARY FROM DISSIPATING CONVECTION OVER E CENTRAL MN.
   SURFACE AIRMASS LOCATED OVER THE WARM SIDE OF THIS BOUNDARY IS
   CHARACTERIZED BY TEMPERATURES IN THE UPPER 60S TO LOWER 70S...WITH
   DEWPOINTS IN LOW TO MID 40S. MODIFIED RUC SOUNDINGS USING THESE
   CONDITIONS YIELD MLCAPE VALUES AROUND 500-1000 J/KG. NEW
   THUNDERSTORM DEVELOPMENT HAS OCCURRED DURING THE LAST HR OR TWO OVER
   CENTRAL-ERN ND...WITH THE STRONGEST CORES LOCATED NEAR JMS MOVING
   ENE AT 20-25 KT. GIVEN THE STEEP MID LEVEL LAPSE RATE ENVIRONMENT
   /AOA 7.5 C PER KM/ AND STRENGTHENING EFFECTIVE BULK SHEAR /DUE TO
   DEEPENING UPDRAFT LAYER/...THESE STORMS MAY BE CAPABLE OF PRODUCING
   LARGE HAIL AND PERHAPS DAMAGING WIND GUSTS. AT THIS TIME...THE
   THREAT IS EXPECTED TO BE TOO MARGINAL TO WARRANT A WW.
   
   ..GARNER.. 05/11/2009
   
   
   ATTN...WFO...FGF...BIS...
   
   LAT...LON   47190095 47900011 48129905 47969817 47589744 47019708
               46449741 46049854 46280012 46670066 47190095