AREAS AFFECTED...PORTIONS NERN MO...CENTRAL IL...CENTRAL/NRN
INDIANA.
CONCERNING...SEVERE THUNDERSTORM WATCH 93...
VALID 110100Z - 110300Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 93
CONTINUES.
SUMMARY...THREAT FOR LARGE HAIL AND SPORADIC STG-DAMAGING GUSTS WILL
CONTINUE N OF BLENDED FRONTAL/OUTFLOW BOUNDARY DELINEATED BELOW.
SOME SRN COUNTIES OF WW OVER PORTIONS SERN IL WILL BE REPLACED WITH
TORNADO WW SHORTLY. REF SPC MESOSCALE DISCUSSION 434 FOR THAT AREA
OF CONCERN AND SWD.
DISCUSSION...SFC MESOANALYSIS SHOWED PRIMARY LOW OVER ERN MO
VICINITY STL...ALONG LEADING EDGE OF NNE-SSW ALIGNED QLCS THAT
EXTENDS FROM WRN IL ACROSS SERN MO INTO ERN AR. STG/QUASISTATIONARY
BAROCLINIC ZONE...REINFORCED BY CUMULATIVE CONVECTIVE OUTFLOWS...WAS
ANALYZED FROM LOW ENEWD PAST IND...GENERALLY ALONG AND JUST N OF
I-70. LITTLE MOTION IS EXPECTED WITH THIS BOUNDARY...N OF WHICH
BOUNDARY LAYER BECOMES VERY STABLE QUICKLY PER 00Z ILX RAOB. STABLE
LAYER IS SHALLOW...HOWEVER...AND UNDERLIES ELEVATED MUCAPE 500-1200
J/KG AND EFFECTIVE SHEAR MAGNITUDES 45-55 KT. LLJ-RELATED
ISENTROPIC LIFT OF PARCELS ATOP FRONTAL SFC TO LFC WILL CONTINUE
AHEAD OF MAIN MCS...SUPPORTING ISOLATED TSTMS WITH HAIL.
QLCS...THOUGH DEPENDENT ON ELEVATED INFLOW OVER THIS AREA...MAY
PUNCH ISOLATED STG-SVR GUSTS THROUGH STABLE LAYER WITHIN 40-50 NM N
OF FRONT.
..EDWARDS.. 04/11/2013
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...ILN...IWX...IND...LOT...ILX...LSX...DVN...
LAT...LON 39119126 40279081 41158706 41128476 39518489 39218723
39598804 39568954 39119126
