MESOSCALE DISCUSSION 1661
   NWS STORM PREDICTION CENTER NORMAN OK
   1157 AM CDT TUE JUL 19 2011
   
   AREAS AFFECTED...SERN MN THROUGH SWRN WI AND EXTREME NERN IA
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 662...
   
   VALID 191657Z - 191830Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 662
   CONTINUES.
   
   THREAT FOR MAINLY ISOLATED DAMAGING WIND AND LARGE HAIL WILL
   CONTINUE AS ONGOING STORMS MOVE SSEWD. ADDITIONAL DEVELOPMENT WILL
   ALSO BE POSSIBLE THIS AFTERNOON FROM SERN MN...NERN IA AND SWRN WI.
   
   QUASISTATIONARY FRONT EXTENDS FROM ERN SD SEWD THROUGH SRN MN INTO
   SRN WI. A LONE SUPERCELL STORM REMAINS JUST NORTH OF THIS BOUNDARY
   NEAR MINNEAPOLIS MOVING SSEWD. THE ATMOSPHERE IS VERY UNSTABLE WITH
   4000-5000 J/KG MLCAPE...BUT WITH EVIDENCE OF A CAPPING INVERSION.
   RADAR DATA SHOW AN OUTFLOW BOUNDARY EXTENDING WWD FROM THE SUPERCELL
   THROUGH S-CNTRL MN. SHALLOW CUMULUS HAS ALSO BEEN INCREASING FROM
   EXTREME SERN MN INTO NERN IA AND SWRN WI IN VICINITY OF THE FRONT.
   THE CAP WILL CONTINUE TO WEAKEN AS TEMPERATURES CLIMB THROUGH THE
   90S AND ADDITIONAL STORMS COULD DEVELOP...ESPECIALLY WHERE THE SWD
   ADVANCING OUTFLOW BOUNDARY INTERSECTS THE FRONT. EFFECTIVE SHEAR
   FROM 40-45 KT WILL CONTINUE TO SUPPORT ORGANIZED STORMS INCLUDING
   SUPERCELLS. AN ISOLATED TORNADO CANNOT BE RULED OUT GIVEN DEGREE OF
   INSTABILITY AS STORMS TRACK SEWD ALONG THE BOUNDARY. HOWEVER...THE
   HODOGRAPH SIZE IN THE 0-1 KM LAYER IS NOT PARTICULARLY LARGE AND IS
   THE PRIMARY LIMITING FACTOR FOR A MORE WIDESPREAD TORNADO THREAT.
   
   ..DIAL.. 07/19/2011
   
   
   ATTN...WFO...ARX...MPX...
   
   LAT...LON   44829242 44479117 43669049 43189094 43689260 44479306
               44829242