[MCD] SWOMCD

Wed Apr 12 17:37:15 UTC 2006

ACUS11 KWNS 121735
SWOMCD
SPC MCD 121735 
OHZ000-MIZ000-INZ000-122000-

MESOSCALE DISCUSSION 0485
NWS STORM PREDICTION CENTER NORMAN OK
1235 PM CDT WED APR 12 2006

AREAS AFFECTED...EXTREME SERN LWR MI...EXTREME NERN IND...NRN/CNTRL
OH

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 121735Z - 122000Z

TSTMS WILL DEVELOP SWD FROM SRN LWR MI INTO EXTREME NERN IND EARLY
THIS AFTN...THEN MOVE EWD AND BECOME STRONGER IN NRN/CNTRL OH AFTER
21Z.  A FEW STORMS MAY PRODUCE DAMAGING WINDS...LARGE HAIL AND
PERHAPS AN ISOLD TORNADO AND A WW MAY BE NEEDED WITHIN THE HOUR.

WELL-DEFINED UPPER VORTICITY CENTER WAS MOVING ACROSS LWR MI AT 30
KTS AND WILL BE OVER SWRN ONTARIO BY 22Z.  TRAILING TROUGH PASSED
THE WLC INDIANA PROFILER AROUND 15Z AND WILL SWING EWD ACROSS SERN
LWR MI AND NRN/CNTRL OH THROUGH EARLY EVENING. CORRESPONDING SFC
REFLECTION...IN THE FORM OF CONVERGENCE...WILL BE THE IMPETUS FOR
TSTM INITIATION FROM SCNTRL/SERN LWR MI INTO NERN IND EARLY THIS
AFTN.

MESOANALYSIS SHOWS A TONGUE OF 50-55 DEGREE F DEW POINTS ADVECTING
NEWD AHEAD OF THE FRONT COINCIDENT WITH THE STEEPEST LOW-LEVEL LAPSE
RATES. THIS WILL BE SUFFICIENT TO SUPPORT TSTMS ALONG/AHEAD OF THE
FRONT THIS AFTN.

TAMDAR/ACAR SOUNDINGS FROM KTOL/KDTW EXHIBIT VERY STRONG LOW-LEVEL
WIND FIELDS WITH 45+ KTS JUST OFF THE SFC...WITH FLOW TURNING WNWLY
ABOVE 3 KM.  THIS IS BOOSTING VERTICAL AND LOW-LEVEL SHEAR VALUES TO
SUPPORT BRIEF SUPERCELL STRUCTURES.  MEAN-SHEAR VECTORS IN THE 2-6KM
LAYER NEARLY NORMAL TO THE INITIATING BOUNDARY SUGGESTS THAT THERE
COULD BE DISCRETE STRUCTURES.  BUT...EVOLUTION INTO A MIX OF LINEAR
AND DISCRETE CELLS WILL BE LIKELY OWING TO STRONG FORCING.  STRONGER
STORMS WILL BE CAPABLE OF LARGE HAIL GIVEN STEEP MID-LEVEL LAPSE
RATES...AND DAMAGING WINDS WILL BE LIKELY.  ISOLD TORNADOES CANNOT
BE RULED OUT GIVEN THE MAGNITUDE OF LOW-LEVEL SHEAR.

..RACY.. 04/12/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PBZ...RLX...CLE...ILN...DTX...IWX...GRR...IND...

40028464 41098545 42288478 42728387 42568300 42148184
41658115 40728064 39948188 39768301 39718411 

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