[MCD] SWOMCD

Sun Dec 4 01:50:21 UTC 2005

ACUS11 KWNS 040147
SWOMCD
SPC MCD 040147 COR
MDZ000-VAZ000-PAZ000-WVZ000-OHZ000-KYZ000-INZ000-040700-

MESOSCALE DISCUSSION 2518
NWS STORM PREDICTION CENTER NORMAN OK
0747 PM CST SAT DEC 03 2005

AREAS AFFECTED...SRN IND/SRN OH/NRN KY/WV/WRN MD/NRN VA

CONCERNING...FREEZING RAIN AND SLEET 

VALID 040147Z - 040700Z

CORRECTED FOR NASHVILLE SOUNDING

...AREAS OF FZRA AND SLEET LIKELY THIS EVENING AND OVERNIGHT OVER
PORTIONS OF THE OH VALLEY INTO THE CNTRL APPALACHIANS...

ELEVATED CONVECTION/OVERRUNNING PCPN IS ALREADY MOVING NORTH OF THE
OH RIVER...WHERE SFC TEMPS ARE AT OR BELOW FREEZING. WARMER
TEMPERATURES WITHIN THE 750-800MB LAYER PER 00Z SOUNDINGS ARE
RESULTING IN FREEZING RAIN ACROSS SRN IND/SRN OH. LARGE SCALE ASCENT
WILL INCREASE AHEAD OF MID LEVEL SHORTWAVE NOW OVER THE UPPER
MIDWEST. LATEST VAD WIND DATA FROM LOUISVILLE AND JACKSON KY
INDICATE AT LEAST A 40-45 KT LLJ AROUND THE 1-2 KM AGL LAYER WITH 50
KT OBSERVED AT 850MB ON THE 00Z NASHVILLE SOUNDING. THE LLJ /850MB
FLOW/ IS FORECAST TO INCREASE TO NEARLY 70KT BY 06Z WHICH WILL
MAINTAIN STRONG WAA/ISENTROPIC LIFT ACROSS SRN OH/WV THIS EVENING. 

AMBIENT AIRMASS AT THE SFC IS VERY DRY...WITH DEWPOINTS IN THE TEENS
IN MANY LOCATIONS. ALL THE SHORT TERM MODELS ARE TOO SLOW WITH
BREAKING OUT PRECIPITATION GIVEN CURRENT TRENDS. HOWEVER RUC/NAM
PTYPE ALGORITHMS DO AGREE THAT FZRA POSSIBLY MIXING WITH SLEET WILL
DEVELOP ACROSS MUCH OF WV/NWRN VA/SRN OH AND POSSIBLY INTO SW PA
THROUGH 04-06Z. FORECAST SOUNDINGS SUGGEST SOME OF THE HEAVIEST FZRA
WILL LIKELY FALL AFTER 06Z ACROSS WV/NRN VA...WITH A STRONG
INVERSION /+2 TO +4C/ NOTED IN THE 850-700MB LAYER ATOP A
SUBFREEZING SFC AIRMASS.

..TAYLOR.. 12/04/2005

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

ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...CLE...JKL...ILN...LMK...IWX...IND...PAH...

37467937 38178286 38498735 39488753 40328719 40157975
39767751 38517797 

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