Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 261909
SWOMCD
SPC MCD 261909
OHZ000-INZ000-ILZ000-262145-

MESOSCALE DISCUSSION 1623
NWS STORM PREDICTION CENTER NORMAN OK
0209 PM CDT TUE AUG 26 2014

AREAS AFFECTED...E-CNTRL IL...CNTRL INDIANA...W-CNTRL/SWRN OH

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 261909Z - 262145Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...THERE WILL EXIST AN INCREASING RISK FOR SVR THUNDERSTORMS
THROUGH THIS AFTERNOON. WHILE WW ISSUANCE IS CURRENTLY
UNLIKELY...CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED. IF A
MORE ORGANIZED/LARGER-SCALE SVR RISK WERE TO EVOLVE...WW PROBABILITY
WOULD INCREASE.

DISCUSSION...STRONG HEATING OF A MOIST BOUNDARY LAYER -- E.G.
LOWER/MIDDLE 70S SFC DEWPOINTS -- OVER THE SRN FLANK OF A LOOSELY
ORGANIZED MCS CROSSING NRN INDIANA AND SRN LOWER MI IS SUPPORTING
MLCAPE AROUND 2000-4000 J/KG. RECENT MOSAIC RADAR IMAGERY SUGGESTS
THAT CONVECTIVE REGENERATION IS FAVORED SWD/SEWD INTO THIS VERY
STRONG INSTABILITY...ESPECIALLY INVOF A REMNANT OUTFLOW BOUNDARY
ARCING FROM E OF FWA TO NEAR LAF. SFC OBSERVATIONS DO NOT INDICATE A
LARGE-SCALE/STRONG COLD POOL SUPPORTING THE ONGOING ACTIVITY...WHICH
CASTS UNCERTAINTY ON FUTURE TRENDS OF THE SVR-TSTM POTENTIAL AMIDST
WEAK SYNOPTIC ASCENT. FURTHERMORE...WITH AREA VWP DATA INDICATING
AOB 15 KT OF MID-LEVEL FLOW/WEAK DEEP SHEAR...OVERALL CONVECTIVE
ORGANIZATION/SUSTENANCE COULD BE LIMITED. REGARDLESS...THE HIGH
DEGREE OF BUOYANCY OFFERS SOME CONCERN FOR INTENSE
UPDRAFTS/DOWNDRAFTS CAPABLE OF LOCALLY DMGG WIND GUSTS AND SVR HAIL.
IF AMALGAMATING COLD POOLS WERE TO BREED UPSCALE GROWTH INTO A
LARGER-SCALE...ORGANIZED CONVECTIVE SYSTEM...THE RISK FOR
GREATER-COVERAGE DMGG WIND GUSTS COULD INCREASE POTENTIALLY
WARRANTING A SVR TSTM WATCH. CONVECTIVE TRENDS WILL CONTINUE TO BE
MONITORED.

..COHEN/MEAD.. 08/26/2014

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

ATTN...WFO...ILN...IWX...IND...LOT...ILX...

LAT...LON   39008650 39158849 39558919 40178902 40498696 40628478
            40168433 39368492 39008650




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