[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 311857
SWOMCD
SPC MCD 311857 
MIZ000-OHZ000-INZ000-ILZ000-312100-

MESOSCALE DISCUSSION 0377
NWS STORM PREDICTION CENTER NORMAN OK
1257 PM CST FRI MAR 31 2006

AREAS AFFECTED...PARTS OF SRN MI...MUCH OF IND...INTO E CNTRL/SRN IL

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 311857Z - 312100Z

AREA IS BEING MONITORED FOR THE POSSIBILITY OF A WW.

DRY SLOT WRAPPING INTO CYCLONE OVER THE UPPER MISSISSIPPI VALLEY IS
ALLOWING FOR AXIS OF STRONG SURFACE HEATING...EAST OF THE OZARK
PLATEAU INTO PARTS OF THE LOWER GREAT LAKES REGION.  MORE
SPECIFICALLY...THERMAL RIDGE AXIS CURRENTLY EXTENDS ACROSS SOUTH
CENTRAL ILLINOIS INTO NORTH INDIANA...WITH MOISTURE RETURN OCCURRING
TO THE EAST...ON SOUTHERLY FLOW OUT OF THE LOWER MISSISSIPPI VALLEY.

NARROW TONGUE OF LOWER 60S DEW POINTS HAS RECENTLY SURGED THROUGH
SOUTHERN ILLINOIS AND LIKELY WILL CONTINUE NORTHWARD THROUGH WESTERN
INTO NORTHERN INDIANA BY LATE AFTERNOON.  DRY LINE STRUCTURE IS
EXPECTED TO SET UP BY AROUND 21Z...PROVIDING A FOCUS FOR VIGOROUS
CONVECTIVE DEVELOPMENT...BEFORE UPSTREAM COLD FRONT ADVANCES INTO
REGION LATER THIS AFTERNOON AND EVENING.

AS INCREASING COOL/CYCLONIC MID-LEVEL FLOW ALSO CONTRIBUTES TO
WEAKENING INHIBITION...SCATTERED THUNDERSTORMS ARE EXPECTED TO
INITIATE LATE THIS AFTERNOON.  THIS SEEMS MOST LIKELY NORTH OF TERRA
HAUTE INTO THE FORT WAYNE AREA...POSSIBLE AS EARLY AS 21Z...BEFORE
ACTIVITY EVENTUALLY DEVELOPS SOUTHWARD TOWARD AREAS OF SOUTHERN
ILLINOIS AROUND MT.VERNON.  GIVEN FAVORABLE CONVECTIVE INSTABILITY
...AND MIXED LAYER CAPE UP TO 1000 J/KG...SHEAR BENEATH 50 TO 70 KT
CYCLONIC MID-LEVEL FLOW WILL BE SUPPORTIVE OF SUPERCELLS.  DESPITE
NEAR UNIDIRECTIONAL FLOW...LOW-LEVEL HODOGRAPHS WILL BE LARGE
BENEATH 50 TO 60 KT 850 JET...AND ISOLATED TORNADOES APPEAR POSSIBLE
IN ADDITION TO RISK FOR LARGE HAIL/DAMAGING WINDS.

..KERR.. 03/31/2006

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

ATTN...WFO...ILN...DTX...LMK...IWX...GRR...IND...PAH...ILX...

41498596 42588468 42398381 40638481 39428601 38668647
38058728 37838847 37998905 38598856 39828763 40198722
40918656 

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