MESOSCALE DISCUSSION 1394
   NWS STORM PREDICTION CENTER NORMAN OK
   1228 PM CDT THU JUL 05 2007
   
   AREAS AFFECTED...ERN WI AND MOST OF MI
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 051728Z - 051930Z
   
   LATEST WATER VAPOR IMAGERY SHOWS THE CORE OF A ROBUST MID-LEVEL
   TROUGH /H5 TEMP MINUS 16 DEG C/ MOVING SEWD THROUGH NERN WI VCNTY
   KGRB.  THE STRONG INSOLATION HAS CONTRIBUTED TO A STEEP LAPSE RATE
   ENVIRONMENT OVER DOWNSTREAM LOCATIONS ACROSS ERN WI AND ACROSS MOST
   OF MI.  GIVEN SFC DEW POINTS IN THE MID 50S TO NEAR 60 DEG F BENEATH
   COLD TEMPERATURES ALOFT...MLCAPES WERE INCREASING INTO THE 500-1000
   J/KG RANGE.
   
   OVERALL MASS CONVERGENCE REMAINS WEAK AND PINPOINTING INITIATION
   POTENTIAL REMAINS QUITE DIFFICULT.  STRONGEST LOW-LEVEL CONVERGENCE
   APPEARS TO BE FAVORING A WEAK WIND SHIFT...TIED TO THE UPR
   IMPULSE... SETTLING SWD INTO CNTRL WI.  CBS HAVE DEVELOPED RECENTLY
   ALONG THIS BOUNDARY OVER NERN WI AND SHOULD CONTINUE TO EXPAND SSEWD
   TOWARD KGRB/KMKE VCNTY THIS AFTN.  OTHER CONVERGENCE ZONES WERE TIED
   TO LAKE BREEZE BOUNDARIES OVER ERN WI AND ACROSS SWRN UPR MI WHERE
   TSTMS SHOULD INITIATE EARLY THIS AFTN.  FINALLY...OTHER STORMS MAY
   BEGIN TO FAVOR LAKE BREEZE BOUNDARIES OVER SWRN AND CNTRL LWR MI.
   
   12 MPX SOUNDING SHOWED A 50 KT JET STREAK ASSOCD WITH THE IMPULSE
   AND CURRENT VWP FROM GREEN BAY EXHIBITED 45 KT FLOW AROUND 4 KM. 
   TROPOSPHERIC FLOW WAS LARGELY UNIDIRECTIONAL WNWLY...SUGGESTING THAT
   MULTICELL STORM CLUSTERS COULD BECOME ORGANIZED INTO LINE SEGMENTS. 
   BUT...GIVEN AT LEAST 30 KTS OF 0-3KM SHEAR...BRIEF SUPERCELL
   STRUCTURES WILL ALSO BE POSSIBLE.  STEEP LAPSE RATES ALOFT AND
   MODEST WIND SHEAR WILL FAVOR LARGE HAIL PRODUCTION AND DMGG WIND
   GUSTS WILL ALSO BE LIKELY AS THE ACTIVITY SPREADS SEWD INTO LWR MI
   LATER THIS AFTN.  PARTS OF THE REGION MAY NEED A WW IF ACTIVITY CAN
   BECOME SUSTAINED AND ORGANIZED.
   
   ..RACY.. 07/05/2007
   
   
   ATTN...WFO...DTX...APX...IWX...GRR...MQT...GRB...MKX...ARX...
   
   46158731 45598443 44998355 44558372 44138406 43838419
   43118367 42438306 42028352 41898439 41798552 42048613
   42528570 43208578 43658598 44418611 44718617 45268557
   45568578 45748645 45768705 45418756 44918741 44168764
   43608780 43298788 42838792 42608799 42928870 44008950
   44528979 45139002 45619003 46028953 46148908 46168796