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000
ACUS11 KWNS 051801
SWOMCD
SPC MCD 051800
INZ000-ILZ000-MOZ000-ARZ000-OKZ000-TXZ000-052300-

MESOSCALE DISCUSSION 2059
NWS STORM PREDICTION CENTER NORMAN OK
1200 PM CST THU DEC 05 2013

AREAS AFFECTED...NCNTRL TX...SERN OK THROUGH NWRN AR...SRN MO...SRN
IL AND SWRN IND

CONCERNING...FREEZING RAIN

VALID 051800Z - 052300Z

SUMMARY...FREEZING RAIN...POSSIBLY MIXED WITH SLEET IN SOME
LOCATIONS WITH RATES FROM .02 INCHES TO LOCALLY IN EXCESS OF .1 INCH
PER HOUR IS EXPECTED TO CONTINUE THROUGH THE AFTERNOON FROM SERN
OK...NWRN AR...SRN MO INTO SRN IL...EVENTUALLY DEVELOPING INTO
PORTIONS OF NCNTRL TX.

DISCUSSION...EARLY THIS AFTERNOON A CORRIDOR OF FREEZING RAIN AND
SOME SLEET PERSISTS FROM ERN OK THROUGH NWRN AR...SRN MO AND SRN IL.
THIS WINTRY MIX IS DEVELOPING IN ASSOCIATION WITH FRONTOGENETIC
FORCING ALONG A SW-NE ORIENTED BAROCLINIC ZONE. A LOW AMPLITUDE
SHORTWAVE TROUGH LOCATED OVER WRN TX WILL CONTINUE NEWD TOWARD THE
LOWER MS VALLEY THIS AFTERNOON AND EVENING. INCREASING SWLY FLOW IN
THE 850-700 MB LAYER AHEAD OF THIS FEATURE WILL AUGMENT FORCING
ALONG THE BAROCLINIC ZONE...LIKELY RESULTING IN POTENTIAL FOR
INCREASING PRECIPITATION RATES. FREEZING RAIN LINE SHOULD GRADUALLY
DEVELOP SLOWLY SWD AS SURFACE TEMPERATURES WET BULB TO AOB FREEZING
AND AS COLDER AIR ASSOCIATED WITH ARCTIC HIGH PRESSURE CENTERED OVER
THE NRN HIGH PLAINS ADVECTS SWD. STRENGTHENING SWLY WINDS ABOVE THE
SUBFREEZING NEAR SURFACE LAYER SHOULD MAINTAIN A WARM NOSE
SUFFICIENT FOR PRECIPITATION TO FALL AS MOSTLY FREEZING RAIN...BUT
WITH SOME SLEET ALSO POSSIBLE. MODEL SOUNDING ALSO INDICATE A
SHALLOW UNSTABLE LAYER ALOFT SUGGESTING PRECIPITATION RATES MAY BE
LOCALLY ENHANCED WITHIN CONVECTIVE ELEMENTS.

..DIAL.. 12/05/2013

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

ATTN...WFO...IND...PAH...ILX...MEG...LSX...LZK...SGF...SHV...
TSA...FWD...OUN...SJT...

LAT...LON   38378724 37678859 36059181 32649810 33279895 36919337
            39008807 38378724