000
FXUS64 KOUN 121747
AFDOUN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
1147 AM CST THU DEC 12 2013

.AVIATION...12 DEC 18Z TAF ISSUANCE...
VFR CEILINGS WILL CONTINUE TO INCREASE THROUGH THE AFTERNOON FROM
SW TO NE. SOUTH WINDS WILL INCREASE SLIGHTLY THROUGH THE
AFTERNOON AS A SFC LOW PRESSURE CENTER CONTINUES TO APPROACH FROM
THE WEST...LIFTING A WEAK WARM FRONT NWRD ACROSS THE SRN PLAINS.
17Z SFC ANALYSIS PLACES THE CENTER OF THE LOW OVER NERN NM/SERN
CO. RAIN CHANCES ACROSS CENTRAL AND ERN OK WILL INCREASE AFTER
MIDNIGHT THROUGH FRIDAY. BEST CHANCES FOR RAIN WILL EXIST ACROSS
ERN OK. THEREFORE... DECIDED TO LEAVE MENTION OUT OF KOKC/KOUN
TAFS FOR THE MOMENT. HOWEVER... DID PLACE MVFR CEILINGS AND TEMPO
OF -RA FOR KPNC AT THE END OF THE TAF PERIOD.

JTK

&&

.PREV DISCUSSION... /ISSUED 417 AM CST THU DEC 12 2013/

DISCUSSION...
SURFACE RIDGE IS MOVING EAST THROUGH THE AREA AND WILL ALLOW
SOUTHERLY WINDS TO RETURN AREAWIDE TODAY AS IT MOVES EAST OF THE
AREA. SLIGHTLY WARMER TEMPERATURES ARE EXPECTED TODAY... BUT WILL
AGAIN BE MODIFIED OVER THE SNOWPACK SOUTHWEST.

THE UPPER LOW COMING ONSHORE NEAR THE CALIFORNIA-BAJA CALIFORNIA
BORDER AREA WILL CONTINUE TO MOVE TOWARD THE AREA WITH INCREASING
MOISTURE AHEAD OF THIS SYSTEM. PRECIPITATION CHANCES WILL BEGIN
JUST BEFORE MIDNIGHT IN THE FAR SOUTHWEST THEN SPREADING NORTHEAST
FRIDAY MORNING. IT CURRENTLY LOOKS LESS LIKELY FOR FREEZING RAIN
ESPECIALLY IF TEMPERATURES SLOWLY RISE OVERNIGHT WITH THE SOUTH
WINDS. BUT MIN TEMPERATURES ARE FORECAST TO BE RIGHT NEAR FREEZING
ACROSS MUCH OF THE AREA AND SUB-FREEZING TEMPERATURES ARE
CERTAINLY WITHIN THE MARGIN OF UNCERTAINTY OF THE FORECAST
TEMPERATURES... SO WILL KEEP THE MENTION OF A SLIGHT CHANCE OF
FREEZING RAIN IN THE ZONES BEFORE SUNRISE FRIDAY MORNING. THE
PRECIPITATION ASSOCIATED WITH THIS SYSTEM MOVES EAST OF THE AREA
ON SATURDAY MORNING. TEMPERATURES WILL WARM TO CLOSER TO SEASONAL
AVERAGES EARLY NEXT WEEK.

THERE IS DISAGREEMENT AMONG THE MEDIUM-RANGE MODELS TOWARD THE END
OF THE FORECAST PERIOD REGARDING HOW MUCH COLD AIR MOVES BACK INTO
THE AREA. GFS IS MORE AMPLIFIED WITH A TROF MOVING SOUTHEAST FROM
THE CANADIAN PRAIRIES INTO THE UPPER MIDWEST OF THE UNITED
STATES... AND THIS AIDS IN COOLER AIR MOVING BACK INTO THE AREA
LATE. THE ECMWF IS MUCH LESS AMPLIFIED AND KEEPS TEMPERATURES
WARMER. THIS FORECAST LEANS TOWARD THE WARMER ECMWF FORECAST.

26

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  43  32  47  30 /   0  20  40  20
HOBART OK         39  30  48  27 /   0  20  20   0
WICHITA FALLS TX  42  35  52  31 /   0  20  40  10
GAGE OK           49  30  54  19 /   0  10  10   0
PONCA CITY OK     42  32  46  25 /   0  20  40  20
DURANT OK         42  33  45  38 /   0  20  60  30

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

$$