FXUS64 KOUN 291150
AFDOUN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
550 AM CST SUN NOV 29 2009
.AVIATION...
PRIMARILY VFR CEILINGS EXPECTED AT TERMINALS...ALTHOUGH MVFR
CEILINGS WILL BE POSSIBLE ACROSS CENTRAL OKLAHOMA AND DOWN AROUND
KLAW/KSPS FOR A FEW HOURS THIS MORNING BEFORE CAA AND DRIER AIR TAKE
OVER BEHIND FRONT. FAIRLY LARGE AREA OF VIRGA AND SCATTERED SHOWERS
EXPECTED TO PROGRESS NORTHEAST FROM WEST TEXAS...AFFECTING MAINLY
SOUTHWEST AND CENTRAL OKLAHOMA TERMINALS WITH 040-060 CEILINGS AND
BRIEF PERIOD OF MVFR VISIBILITY RESTRICTIONS. STRONG NORTHERLY WINDS
WILL SUBSIDE LATE THIS AFTERNOON AND BECOME LIGHT MOST AREAS THIS
EVENING...COINCIDING WITH RAPID CLEARING FROM NORTH TO SOUTH.
&&
.DISCUSSION...
COLD FRONT CONTINUES TO MAKE DECENT PROGRESS OVER THE REGION EARLY
THIS MORNING...AND IS STILL EXPECTED TO EXIT SOUTHEAST OKLAHOMA
PORTION OF OUR CWA EARLY THIS AFTERNOON. WILL BE FAIRLY GUSTY
BEHIND FRONT FOR SEVERAL HOURS MOST LOCATIONS...BUT WINDS EXPECTED
TO STAY BELOW ADVISORY LEVELS. IT WILL FEEL PRETTY RAW GIVEN THE
RECENT WARM TEMPS.
SOMEWHAT DIFFICULT FORECAST GIVEN SIGNIFICANT SPREAD AMONG
MODELS...ESPECIALLY IN THE SHORT-TERM. GFS MUCH MORE AGGRESSIVE
WITH MOISTENING/LIFT AND ASSOCIATED RAINFALL TODAY...WITH THE WRF
MUCH...MUCH DRIER. EACH RESPECTIVE MODEL STICKING TO ITS GUNS ON
THE 06Z RUN. WE WILL BE SIDING MORE WITH THE WETTER GFS...DESPITE
CURRENT ENVIRONMENT OF VERY DRY AIR ALOFT AND INTRUSION OF DRY AIR
NEAR THE SURFACE BEHIND FRONT. MODERATE TO STRONG LIFT IN EXIT
REGION OF STRONG UPPER JET...COMBINED WITH 750-650FG HAS ALLOWED
MOISTENING OF UPSTREAM AIRMASS ACROSS WEST TEXAS...AND THE GFS
HAS A MUCH BETTER HANDLE OF PRECIP REACHING THE GROUND AT THIS
TYPING. A MAJORITY OF THE PRECIPITATION WILL BE VERY LIGHT...
PERHAPS MORE LIKE SPRINKLES...BUT AT LEAST CHANCE POPS WARRANTED.
THERE WILL BE A CHANCE FOR AN ENHANCED BAND OF LIGHT-MODERATE
RAIN ACROSS WEST-CENTRAL INTO CENTRAL OKLAHOMA FOR A FEW HOURS
LATER THIS MORNING AND THIS AFTERNOON NEAR ZONE OF FG FORCING. WE
WILL CARRY HIGHER GFS POPS IN THIS ZONE AND ACROSS SOUTHEAST
OKLAHOMA CLOSER TO LOWER LEVEL BAROCLINIC ZONE.
UPPER LOW STILL FORECAST TO PROGRESS EASTWARD INTO NORTHERN
PORTIONS OF TEXAS LATE TUESDAY AND WEDNESDAY. ECM THE MOST
AGGRESSIVE...AND APPEARS TO BE THE MOST CONSISTENT...IN IMPACTING
WESTERN NORTH TEXAS AND SOUTHERN OKLAHOMA WITH PRECIPITATION. WE
WILL BUMP POPS UP ACROSS THE SOUTHERN HALF OF OKLAHOMA AND NORTH
TEXAS TUESDAY THROUGH WEDNESDAY. ANY CHANGE OVER TO FROZEN
PRECIPITATION WILL LIKELY BE CONFINED TO COLD CORE OF UPPER SYSTEM
WHICH MAY SKIRT WESTERN NORTH TEXAS AND THE RED RIVER VALLEY OF
OKLAHOMA. AT THIS POINT...WE WILL BE KEEPING PRECIPITATION ALL IN
LIQUID FORM...BUT A MIX COULD BE INTRODUCED IF MODEL SUITES OF A
MORE NORTHWARD TRACK CONTINUES.
FOR LATE WEEK INTO NEXT WEEKEND...FORECAST WILL FOLLOW ECM MUCH
LIKE HPC GUIDANCE AND SURROUNDING OFFICES. THIS WILL RESULT IN
DRY CONDITIONS BUT TEMPS SEVERAL DEGREES COOLER THAN GFS/MEX
NUMBERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 50 36 58 30 / 60 10 0 0
HOBART OK 48 31 57 32 / 50 10 0 0
WICHITA FALLS TX 54 34 60 34 / 40 10 0 10
GAGE OK 49 23 58 29 / 20 0 0 0
PONCA CITY OK 52 30 57 32 / 20 10 0 0
DURANT OK 60 39 59 37 / 60 30 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/11
