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000
ACUS11 KWNS 060025
SWOMCD
SPC MCD 060025
OHZ000-INZ000-KYZ000-ILZ000-MOZ000-ARZ000-OKZ000-060500-

MESOSCALE DISCUSSION 2060
NWS STORM PREDICTION CENTER NORMAN OK
0625 PM CST THU DEC 05 2013

AREAS AFFECTED...SRN OZARKS NEWD INTO THE LOWER OH VALLEY

CONCERNING...WINTER MIXED PRECIPITATION

VALID 060025Z - 060500Z

SUMMARY...A SW-NE ORIENTED SWATH OF WINTER MIXED PRECIPITATION WILL
PERSIST OVER THE NEXT SEVERAL HRS...WITH A NARROW TRANSITION ZONE
FROM FZRA TO SLEET AND SNOW LIKELY TO BE MAINTAINED. PRECIPITATION
RATES MAY INCREASE NEWD OVER THE NEXT FEW HRS...PARTICULARLY INTO
THE LOWER OH VALLEY.

DISCUSSION...A PERSISTENT BAND OF LIGHT TO MODERATE
PRECIP...CONTAINING MIXED P-TYPES...REMAINS CENTERED OVER NWRN
AR/SRN MO AND INTO SRN IL...OCCURRING WITHIN A CORRIDOR OF ENHANCED
MIDLEVEL MOISTURE AND NEAR A LOW-LEVEL FRONTOGENETIC ZONE. AS OF
00Z...THE SFC FREEZING LINE WAS LOCATED FROM NEAR FSM NEWD TO POF TO
EVV. PREDOMINANT P-TYPE NEAR AND IN THE IMMEDIATE WAKE OF THE SFC
FREEZING LINE SHOULD CONTINUE TO BE FREEZING RAIN...AS WARM NOSE
LOCATED NEAR/ABOVE 850 MB IS MAINTAINED BY 40-50 KT OF SWLY FLOW
/PER LZK AND HPX VWP/ ATOP A LOW-LEVEL COLD DOME. A SHARP
TEMPERATURE GRADIENT IN THE LOWEST 3 KM AGL IS SUPPORTING A
TRANSITION TO MAINLY SNOW AND/OR SLEET TOWARDS THE NRN EDGE OF THE
PRECIP SWATH. OBSERVED LIQUID EQUIVALENT PRECIP RATES HAVE LARGELY
BEEN ON THE ORDER OF .05-0.1 INCH PER HR.

A SUBTLE IMPULSE IS CURRENTLY PROGRESSING NEWD OUT OF OK AND SHOULD
AID IN MAINTAINING LIGHT TO MODERATE PRECIP RATES IN THE NEAR-TERM.
LOW-LEVEL FRONTOGENESIS MAY INCREASE SLIGHTLY AHEAD OF THIS FEATURE
INTO SERN MO AND SRN IL/IND...SUPPORTING INCREASING PRECIPITATION
RATES ACROSS THESE AREAS THROUGH 05Z. BOTH OBSERVATIONAL AND MODEL
TRENDS SUGGEST THE SFC FREEZING LINE SHOULD REMAIN NEARLY STATIONARY
OR JOG SLIGHTLY SWD...MAINTAINING A RELATIVELY NARROW P-TYPE
TRANSITION ZONE.

A MORE SIGNIFICANT IMPULSE ROUNDING THE BASE OF THE WRN CONUS
LARGE-SCALE TROUGH IS FORECAST TO EJECT NEWD ACROSS THE SOUTHWEST
AND SRN HIGH PLAINS TONIGHT INTO EARLY FRI MORNING...AND COULD
SUPPORT INCREASING RATES OVER THE SRN OZARKS BEYOND 05Z.

..ROGERS.. 12/06/2013

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

ATTN...WFO...ILN...LMK...IWX...IND...PAH...ILX...MEG...LSX...
LZK...SGF...TSA...

LAT...LON   37188861 35159161 35159422 35639445 36869463 38129204
            39638858 40358677 40438545 40118475 39588490 38308654
            37188861