MESOSCALE DISCUSSION 1160
   NWS STORM PREDICTION CENTER NORMAN OK
   0326 PM CDT TUE JUN 16 2009
   
   AREAS AFFECTED...S-CENTRAL ND AND N-CENTRAL/NERN SD
   
   CONCERNING...TORNADO WATCH 434...
   
   VALID 162026Z - 162130Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 434 CONTINUES.
   
   THE THREAT FOR LARGE HAIL/DAMAGING WINDS AND TORNADOES CONTINUES FOR
   WW 434. AT 20Z...HI RES RADAR IMAGERY SHOWED A LINE OF STRONG TO
   SEVERE THUNDERSTORMS FROM ROUGHLY MBG TO JUST W OF HON. THESE STORMS
   HAVE DISPLAYED OCCASIONAL STRONG LOW/MID LEVEL ROTATION...AS WELL AS
   REFLECTIVITY SIGNATURES SUGGESTIVE OF LARGE HAIL POTENTIAL.
   SUBJECTIVE SURFACE ANALYSIS INDICATES THE PRESENCE OF A SURFACE LOW
   INVOF MBG...WITH A WIND SHIFT LINE EXTENDING S TOWARD N CENTRAL
   NEB...AND A POSSIBLE WARM FRONT EXTENDING ESE FROM THE LOW TOWARD
   FSD. THE BOUNDARY LAYER AIRMASS ALONG AND W OF THE WIND SHIFT LINE
   CONTINUES TO WARM AND DESTABILIZE...AND WHEN JUXTAPOSED WITH A
   TONGUE OF LOW TO MID 60S DEWPOINTS RESIDING OVER THE ERN HALF OF
   SD...SHOULD CONTINUE TO AID IN THE DEVELOPMENT OF MODERATE
   INSTABILITY /1500-2500 J PER KG OF MLCAPE/ DURING THE NEXT SEVERAL
   HOURS.
   
   AREA VWP/S INDICATE DEEP LAYER SHEAR SUPPORTIVE OF SUPERCELL
   THUNDERSTORMS...AS WELL AS RATHER STRONG LOW LEVEL SHEAR /0-1 KM SRH
   AOA 100 M2 PER S2/ ALONG AND E OF THE WARM FRONT. THESE FAVORABLE
   SHEAR PROFILES /AND STRONG VERTICAL VORTICITY NEAR THE SURFACE LOW/
   COMBINED WITH SUBSTANTIAL CAPE IN THE LOWEST FEW KM/S OF THE
   ATMOSPHERE WILL CONTINUE TO SUPPORT A THREAT OF ISOLATED TORNADOES
   DURING THE AFTERNOON. IN ADDITION...COLD MID LEVEL
   TEMPERATURES/STEEP LOW-MID LEVEL LAPSE RATES WILL ALSO FAVOR LARGE
   HAIL WITH THE STRONGER UPDRAFT CORES.
   
   ..GARNER.. 06/16/2009
   
   
   ATTN...WFO...FGF...FSD...ABR...BIS...
   
   LAT...LON   46850227 46869890 44619644 44599851 44169854 44209931
               44639935 44629971 46850227