AREAS AFFECTED...CNTRL/SRN OH...CNTRL/SRN IND...CNTRL/SRN IL...NRN
KY
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 302255Z - 010130Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...SRN IL/IND/OH AND NRN KY ARE BEING MONITORED FOR POSSIBLE
SVR TSTM WATCH ISSUANCE THROUGH THE EVENING...WHILE THE SVR THREAT
WILL BE MUCH LOWER FARTHER NORTH FROM CNTRL IL TO CNTRL OH.
DISCUSSION...LATEST SFC MESOANALYSIS PLACES A WAVY QUASI-STATIONARY
FRONT EXTENDING FROM 20 WNW QUINCY IL TO 25 SE BLOOMINGTON IND TO
JUST SOUTH OF CINCINNATI OH TO NEAR CHARLESTON WV. TO THE NORTH OF
THIS FRONT...A 1011-MB SFC MESO-HIGH AND ASSOCIATED W-E-ORIENTED
MESO-RIDGE LIES FROM CNTRL IL TO CNTRL OH...AND IS THE RESULT OF
MULTIPLE ROUNDS OF CONVECTIVE OVERTURNING DURING THE PAST 30
HOURS...WITH REINFORCEMENT PROVIDED BY ONGOING CONVECTIVE DEBRIS
CLOUDS/SHOWERS/ISOLATED ELEVATED STORMS. ABUNDANT INHIBITION
COLOCATED WITH THE MESO-HIGH/RIDGE WILL LARGELY MITIGATE ANY SVR
THREAT FROM CNTRL IL EWD TO CNTRL OH.
MEANWHILE...WEAK WAA/ISENTROPIC ASCENT AND THE GLANCING INFLUENCE OF
A MID-LEVEL SHORTWAVE TROUGH ARE SUPPORTING A 20-MILE
WIDE...W-E-ELONGATED SEMI-ORGANIZED BAND OF CONVECTION ACROSS CNTRL
IL. WHILE CNTRL IL 0.5-DEGREE RADAR REFLECTIVITY DATA INDICATE
OUTFLOW LYING WELL IN ADVANCE OF PARENT CONVECTION -- SUGGESTING
ANAFRONTAL CHARACTER TO THE BAND -- MLCAPE VALUES OF 2500-3000 J/KG
PER MODIFIED CENTRAL IL 12Z RAOB COULD SUPPORT ADDITIONAL
DEVELOPMENT OF ONGOING ACTIVITY. SHOULD MORE STORMS DEVELOP AND A
LARGER COLD POOL BECOME ESTABLISHED...THEN A MESOSCALE CONVECTIVE
SYSTEM AND ASSOCIATED SVR THREAT COULD TRACK ESEWD INVOF THE FRONT
GIVEN 30-40 KT OF 0-6-KM BULK SHEAR PER WILMINGTON OH...INDIANAPOLIS
IND...AND CNTRL IL VWP DATA. THIS CONDITIONAL POTENTIAL WOULD
INCLUDE SRN IL/IND/OH AND NRN KY. HOWEVER...LARGE UNCERTAINTY IN
UPSCALE CONVECTIVE GROWTH EXISTS OWING TO THE ABSENCE OF STRONGER
FORCING FOR ASCENT...AS WELL AS THE LACK OF BOUNDARY-LAYER CU PER
VISIBLE SATELLITE IMAGERY ACROSS THE OH VALLEY -- PERHAPS INDICATING
ABUNDANT DRY AIR/INHIBITION THROUGH THE BOUNDARY LAYER.
..COHEN/HART.. 06/30/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PBZ...RLX...CLE...JKL...ILN...LMK...IWX...IND...
PAH...LOT...ILX...LSX...
LAT...LON 37918473 37878614 38158802 38998988 39998993 40488865
40618812 40778692 40768580 40538284 39918220 38658229
37978358 37918473
