[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 082331
SWOMCD
SPC MCD 082330 
OHZ000-MIZ000-INZ000-ILZ000-WIZ000-IAZ000-090100-

MESOSCALE DISCUSSION 2393
NWS STORM PREDICTION CENTER NORMAN OK
0530 PM CST TUE NOV 08 2005

AREAS AFFECTED...PORTIONS E-CENTRAL/SERN IA...CENTRAL/NRN
IL...CENTRAL/NRN INDIANA...SRN LOWER MI...SRN LM...SRN WI...WRN OH.

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 082330Z - 090100Z

POTENTIAL FOR SEVERE TSTM DEVELOPMENT WILL INCREASE DURING NEXT FEW
HOURS IN A WNW-ESE ORIENTED CORRIDOR MAINLY OVER CENTRAL/NRN
PORTIONS IL/INDIANA.  THREAT MAY EXTEND AS FAR W AS MS RIVER REGION.
 TORNADO WW AND SEPARATE SEVERE TSTM WW FARTHER N ARE BEING PREPARED
ATTM.

SFC MESOANALYSIS SHOWS DOUBLE STRUCTURED WARM FRONTAL ZONE ACROSS
REGION.  SOUTHERN  BOUNDARY -- REINFORCED INITIALLY BY DIFFERENTIAL
DIURNAL HEATING/MIXING -- IS EVIDENT FROM SWRN IA ESEWD ACROSS NERN
MO...SRN IL...EVV/OWB REGION...INTO E-CENTRAL KY.  EXPECT THIS FRONT
TO LOSE DEFINITION AND CONSOLIDATE NWD AMIDST CONTINUED BOUNDARY
LAYER WAA AND PRESSURE FALLS FARTHER NW.  NRN FRONTAL SEGMENT IS
STRENGTHENING FROM TRIPLE POINT LOW IN NERN SD...SEWD ACROSS CENTRAL
IA THEN ESEWD OVER CENTRAL IL/INDIANA JUST N OF AN SPI-IND
LINE...BECOMING DIFFUSED BY OUTFLOW EWD TO NEAR HTS.  LATTER FRONTAL
SEGMENT SHOULD MOVE NWD ABOUT 10 KT.

MODIFIED 18Z ILX RAOB AND RUC SOUNDINGS INDICATE POTENTIAL FOR ANY
TSTMS ALONG OR IN NARROW CORRIDOR IMMEDIATELY N OF FRONT TO BE
NEARLY SFC-BASED....INFLOW LAYER BECOMING INCREASINGLY ELEVATED WITH
NWD EXTENT FROM WARM FRONTOGENESIS ZONE.  ACCORDINGLY...SFC DEW
POINTS LOW 60S F CONTRIBUTE TO MLCAPE AROUND 1500 J/KG ALONG AND S
OF NRN FRONT...TRANSITIONING TO ELEVATED MUCAPES 1500-2000 J/KG
WITHIN ABOUT 75 NM N OF NRN WARM FRONT SEGMENT.  SBCINH INCREASES
WITH WWD EXTENT BENEATH STRONGER ELEVATED MIXED LAYER...SO POTENTIAL
FOR SFC-BASED TSTMS IS MORE UNCERTAIN OVER WRN IL AND ERN IA THAN
FARTHER E.  VERTICAL SHEAR PROFILES SUPPORT SUPERCELL MODES...WITH
DAMAGING GUSTS AND SLGT RISK FOR TORNADOES INVOF FRONT...AND LARGE
HAIL BEING MOST DOMINANT THREAT WELL N OF FRONT. STRONG CURVATURE IN
HODOGRAPHS ALONG/N OF FRONT AND 40-50 KT MIDLEVEL WNWLYS SUPPORT 0-1
KM SRH 125-250 J/KG AND 0-6 KM SHEARS ABOUT 60 KT.

..EDWARDS.. 11/08/2005

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

ATTN...WFO...CLE...ILN...DTX...IWX...GRR...IND...GRB...LOT...ILX...MKX...DVN...ARX...

39488622 40118963 40729170 41489146 43039054 44138961
43758724 42638344 41398299 39958356 39558428 

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