[MCD] SWOMCD

Fri Sep 22 22:37:11 UTC 2006

ACUS11 KWNS 222237
SWOMCD
SPC MCD 222237 
INZ000-ILZ000-WIZ000-230030-

MESOSCALE DISCUSSION 2012
NWS STORM PREDICTION CENTER NORMAN OK
0537 PM CDT FRI SEP 22 2006

AREAS AFFECTED...NRN IL...NWRN IND AND SWRN MI

CONCERNING...TORNADO WATCH 791...

VALID 222237Z - 230030Z

CLUSTER OF SUPERCELLS WILL CONTINUE TO MOVE EWD ACROSS NRN IL...WITH
THE MOST ORGANIZED TORNADO THREAT ANTICIPATED OVER THE CHI METRO
AREA THROUGH 00Z. ELEVATED SVR HAIL THREAT MAY DEVELOP NEWD INTO
SWRN MI AND NWRN IND OVER THE NEXT SEVERAL HRS...BUT A NEW WW IS NOT
ANTICIPATED FOR THOSE AREAS ATTM. 

SURFACE ANALYSIS AND RADAR IMAGERY FROM CHICAGO INDICATES A E-W
ORIENTED BOUNDARY EXTENDING FROM NEAR ORD EWD TO JUST NORTH OF ARR.
THREE SEPARATE SUPERCELLS WILL MOVE ALONG AND JUST NORTH OF THIS
BOUNDARY. RECENT LOT VWP DATA SHOWED A STRONGLY CURVED LOW LEVEL
HODOGRAPH WITH O-1 KM SRH AROUND 350 M2/S2. THREAT FOR
TORNADOES...POSSIBLY SIGNIFICANT...WILL OCCUR WITH THESE SUPERCELLS
AS THEY MOVE EWD ALONG AND INTERACT WITH THE AFOREMENTIONED
BOUNDARY. FARTHER SOUTH MORE DISORGANIZED BROKEN LINE OF SUPERCELLS
SHOULD CONTINUE TO MOVE EWD AROUND 30 KTS IN THE PONTIAC AND
BLOOMINGTON AREAS. IN ADDITION TO ISOLATED TORNADO POTENTIAL IN THIS
AREA...STRONG MID LEVEL WINDS /STRAIGHT LINE HODOGRAPH/ WILL FAVOR
ISOLATED LEFT MOVING SUPERCELLS WITH THE THREAT FOR LARGE HAIL.
STRENGTHENING SWLY LOW LEVEL JET WILL AID IN INCREASING ELEVATED
INSTABILITY INTO NWRN IND AND SWRN MI OVER THE NEXT FEW HRS. THIS
MAY SUPPORT A MARGINAL ELEVATED SVR HAIL THREAT WITH ANY DEVELOPING
TSTMS OVER THE AREA AND/OR NRN IL SVR STORMS THAT MOVE INTO THE AREA
IN THE NEXT SEVERAL HRS.

..CROSBIE.. 09/22/2006

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

ATTN...WFO...IND...LOT...ILX...MKX...DVN...

42508756 42528922 41859015 40219068 40268979 40278832
40298738 41028738 42448724 