[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 131931
SWOMCD
SPC MCD 131930 
INZ000-ILZ000-132130-

MESOSCALE DISCUSSION 1647
NWS STORM PREDICTION CENTER NORMAN OK
0230 PM CDT TUE JUL 13 2004

AREAS AFFECTED...ERN IL AND WRN/CNTRL IND

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 131930Z - 132130Z

TSTM POTENTIAL INCREASINGLY RAPIDLY ALONG INTENSE INSTABILITY
GRADIENT ACROSS THE UPPER MIDWEST. A WATCH WILL BE ISSUED SHORTLY TO
REPLACE TORNADO WATCH 619 AND EXTEND ACROSS PARTS OF ERN IL AND
CNTRL IND.

CONVECTION APPEARS TO BE INCREASING IN COVERAGE ON THE NOSE OF
DIFFLUENT MID LEVEL JET STREAK DEVELOPING SEWD ACROSS THE UPPER MS
VALLEY. EXTREME INSTABILITY FEEDING INTO THE REGION OF FAVORABLE
ASCENT WILL FUEL VIGOROUS TSTMS INTO THE EVENING. SUPERCELLULAR
ACTIVITY NOW MOVING SEWD FROM NRN IL WILL CONTINUE TO POSE A THREAT
OF VERY LARGE HAIL AND PERHAPS TORNADOES. FARTHER EAST...INSTABILITY
AND SHEAR PARAMETERS ARE CURRENTLY WEAKER...BUT SHOULD CONTINUE TO
INCREASE OVER THE NEXT FEW HOURS AS THE MID LEVEL WIND MAX AND UPPER
TROUGH DIG SEWD TOWARD THE MIDWEST. IL STORMS MAY EVENTUALLY MERGE
INTO A SEVERE MCS WITH WIND AND HAIL THREAT SPREADING SSEWD ALONG
THE INSTABILITY GRADIENT AND INTO SRN PARTS OF IND BY EVENING.

..CARBIN.. 07/13/2004

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

ATTN...WFO...IWX...IND...LOT...ILX...

40808755 41098587 39298538 38758838 40558887 

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