FXUS64 KOUN 232151
AFDOUN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
351 PM CST WED DEC 23 2009
.DISCUSSION...
HAVE UPGRADED THE NORTHERN AND WESTERN AREAS OF OKLAHOMA TO A
WINTER STORM WARNING AND ALREADY HAVE ISSUED THE WSW. 12Z MODELS
CONTINUED THE OVERNIGHT TREND OF A WETTER/SNOWIER FORECAST WITH
THE EXPECTED TRACK OF THE UPPER LOW AND LESS LIKELIHOOD OF THE DRY
SLOT SLOWING DOWN THE SHOW. ON THE POSITIVE SIDE... THE PRIMARY
NUMERIC MODELS ARE ON THE SAME PAGE WITH THE TIMING OF THE
SWITCHOVER FROM RAIN TO SNOW. BOTH THE NAM AND GFS TIME-HEIGHT
SECTIONS DO SHOW BRIEF PERIODS OF SOMEWHAT DRIER AIR IN THE
DENDRITIC GROWTH TEMPERATURES ELEVATIONS... SO THERE COULD BE A
BRIEF PERIOD OF FREEZING RAIN OR FREEZING DRIZZLE. SLEET IS NOT
OUT OF THE QUESTION IN NORTHERN OKLAHOMA BUT HAVE NOT INCLUDED
THIS IN THE PACKAGE SINCE IT WOULD BE A MINOR ISSUE COMPARED TO
THE SNOW/FREEZING PRECIP. AS COLD AIR ADVECTS INTO THE AREA... WE
CAN SEE THE PROFILE SUPPORTING SNOW IN NORTHWEST OKLAHOMA EARLY
THIS EVENING... TO THE ENID TO FORT COBB TO VERNON AREAS BY 06Z...
AND TO STILLWATER TO NORMAN TO WICHITA FALLS BY ABOUT 12Z.
OF COURSE THE MODELS DO HAVE DIFFERING OPINIONS ON SNOW AMOUNTS
AND THE AXIS OF HEAVIEST SNOW. THINK THE 12Z GFS WAS TOO
AGGRESSIVE AND HAVE GENERALLY GONE BETWEEN THE FORECAST AMOUNTS
FROM THE GFS AND NAM... ALTHOUGH SOMEWHAT ON THE LIGHTER SIDE
GIVEN THE OVERALL PATTERN EVOLUTION AND THE TENDENCY FOR THE MODEL
SNOW GRID FIELDS TO BEGIN ACCUMULATING SNOW TOO EARLY WHEN THE
PRECIP IS STILL FALLING AS RAIN INITIALLY. BUT THE FORECAST AMOUNTS
ARE STILL ENOUGH TO JUSTIFY A WINTER STORM WARNING ACROSS NORTHERN
PORTIONS OF THE AREA. THE STRONG WINDS ON THE BACK SIDE OF THE
SURFACE LOW WILL BE STRONG AND GUSTY TONIGHT INTO TOMORROW CAUSING
BLOWING SNOW AND NEAR-BLIZZARD CONDITIONS. AGAIN THINK THE GFS IS
A LITTLE TOO AGGRESSIVE WITH WIND SPEEDS GIVEN IT'S DEEPER SURFACE
LOW FARTHER WEST THAN OTHER MODELS... BUT IT WILL STILL BE QUITE
WINDY. PRECIP WILL DIMINISH ACROSS MUCH OF THE AREA TUESDAY NIGHT
ALTHOUGH LINGERING SNOW WILL STILL BE POSSIBLE IN THE NORTH INTO
FRIDAY NIGHT AS UPPER LOW ONLY SLOWLY MOVES FROM KANSAS TOWARD
IOWA.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 31 32 19 35 / 90 90 30 10
HOBART OK 29 31 20 35 / 90 70 10 0
WICHITA FALLS TX 34 36 24 40 / 90 60 10 10
GAGE OK 21 26 12 30 / 70 50 10 0
PONCA CITY OK 30 30 12 29 / 90 90 50 20
DURANT OK 40 41 23 39 / 90 80 20 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM CST THURSDAY
FOR OKZ008-013-019-020-025-026.
WINTER STORM WARNING UNTIL 6 PM CST THURSDAY FOR OKZ004>007-
009>012-014>018-021>024-033>035.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST
THURSDAY FOR OKZ027>030-036>041-044>046.
WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST THURSDAY FOR
OKZ031-032-042-043-047-048-050>052.
TX...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST
THURSDAY FOR TXZ083>090.
&&
$$
