Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 141315
SWOMCD
SPC MCD 141314
KYZ000-TNZ000-INZ000-ILZ000-MOZ000-141815-

MESOSCALE DISCUSSION 0096
NWS STORM PREDICTION CENTER NORMAN OK
0714 AM CST SUN FEB 14 2016

AREAS AFFECTED...PORTIONS OF SRN IL...FAR SRN INDIANA...WRN/CNTRL
KY...FAR NRN TN...FAR SERN MO

CONCERNING...WINTER MIXED PRECIPITATION

VALID 141314Z - 141815Z

SUMMARY...A MIX OF SNOW...SLEET...AND FREEZING RAIN WILL CONTINUE
SPREADING EWD ACROSS PARTS OF THE MIDDLE MS VALLEY AND LOWER OHIO
VALLEY THIS MORNING. LOCALLY HEAVY SNOW WILL BE POSSIBLE.

DISCUSSION...AREA RADAR IMAGERY AND LIGHTNING DATA REVEAL A
BLOSSOMING OF CONVECTIVELY ENHANCED PRECIPITATION WITH EMBEDDED
THUNDERSTORMS OVER THE OZARKS AND VICINITY DURING THE PAST SEVERAL
HOURS. THE 12Z SGF RAOB SAMPLED AROUND 150 J/KG OF MUCAPE FOR A
PARCEL ROOTED AROUND 850 MB...WITH A STRONGLY VEERING WIND PROFILE
WITH HEIGHT IMPLYING WAA-DRIVEN ASCENT. PRESENTLY...THE
AFOREMENTIONED PRECIPITATION IS SPREADING EWD TOWARD THE CONFLUENCE
OF THE MS AND OH RIVERS...WITH REPORTS OF FREEZING RAIN AND SLEET
ACROSS PARTS OF CNTRL/SRN MO. THIS IS A MANIFESTATION OF THE
ELEVATED WARM LAYER SAMPLED BY THE SGF RAOB...WHICH HAS BEEN
SUPPORTING UPSTREAM WINTER MIXED PRECIP TYPES AS ADDRESSED IN SWOMCD
0095.

SPATIAL INTERPOLATION OF THERMAL FIELDS BETWEEN 12Z ILX AND SGF
RAOBS SUGGESTS THAT THIS PRECIP WILL CONTINUE DEVELOPING INTO
PROGRESSIVELY COLDER PROFILES ALOFT. THIS WILL SUPPORT AN
EWD-SPREADING BAND OF SNOW FROM PARTS OF SRN IL/INDIANA AND
WRN/CNTRL KY DURING THE MORNING. FRONTOGENETIC ASCENT RELATED TO THE
INTERACTION OF AN APPROACHING MID-LEVEL SHORTWAVE IMPULSE AND
LOW-LEVEL BAROCLINICITY WILL SUPPORT LOCALLY HEAVY SNOW WITHIN THIS
BAND...WITH SNOWFALL RATES POTENTIALLY REACHING NEAR 1 INCH PER HOUR
IN SOME LOCATIONS.

OTHERWISE...A TRANSITION ZONE WILL CONTINUE TO FLANK THE SRN END OF
THE PRECIP SHIELD FROM PARTS OF SERN MO TO FAR WRN KY AND EWD ALONG
THE TN/KY BORDER VICINITY. IN THIS REGION...PARTIAL TO COMPLETE
MELTING OF DESCENDING HYDROMETEORS WITHIN THE WAA-ENHANCED ELEVATED
WARM LAYER WILL RE-FREEZE AS THEY INTERACT WITH SUB-FREEZING
BOUNDARY-LAYER TEMPERATURES. FREEZING-RAIN RATES OF 0.02 TO 0.05
INCH PER HOUR AND SLEET-ACCUMULATION RATES TO ONE-TENTH INCH PER
HOUR WILL BE POSSIBLE -- HIGHEST IN CONVECTIVE CELLS POTENTIALLY
WITH LIGHTNING.

ALL OF THE AFOREMENTIONED ACTIVITY WILL SPREAD EWD THROUGH THE
MORNING...AS CONVECTIVE PRECIP REGENERATION IS SUSTAINED ACROSS
PARTS OF THE OZARKS AND VICINITY.

..COHEN.. 02/14/2016

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

ATTN...WFO...LMK...OHX...PAH...MEG...

LAT...LON   36578962 37418986 37908958 38088866 37888720 37398571
            36758550 36468625 36418890 36578962



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