FXUS64 KOUN 031203
AFDOUN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
603 AM CST THU DEC 3 2009

.AVIATION...
VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. MID-LEVEL
CLOUDS ARE SPREADING INTO THE AREA FROM THE WEST AND THERE WILL BE
SOME VIRGA ASSOCIATED WITH THIS CLOUDS ACROSS WEST CENTRAL AND
SOUTHWEST OKLAHOMA AND KSPS TODAY AND TONIGHT. THERE WILL BE A
SLIGHT CHANCE OF SOME OF THIS REACHING THE GROUND AS -SN AT KSPS
OVERNIGHT BUT CHANCES ARE TOO LOW FOR A PROB30 GROUP.

&&

.PREV DISCUSSION... /ISSUED 347 AM CST THU DEC 3 2009/ 

DISCUSSION...
MID-LEVEL CLOUDS AND RADAR ECHOES ARE ADVANCING EAST FROM THE
TEXAS PANHANDLE... ALTHOUGH THE RADAR ECHOES ARE MAINLY VIRGA.
THIS MID-LEVEL MOISTURE WILL SPREAD INTO THE AREA TODAY AS WELL AS
RADAR ECHOES /BUT STILL AS VIRGA WITH DRY LOW-LEVEL AIR./ WILL
MENTION THAT POSSIBILITY OF FLURRIES OR SPRINKLES IN PORTIONS OF
THE SOUTHWEST THIS AFTERNOON BUT THINK CHANCE OF MEASURABLE PRECIP
IS LOW. AS UPPER TROF PIVOTS OVER THE AREA TONIGHT/TOMORROW...
WILL KEEP SLIGHT CHANCE POPS IN THE SOUTHWEST AND PORTIONS OF THE
SOUTH ALTHOUGH THE MAIN FORCING REMAINS TO THE SOUTH OF THE CWA AND
LOW LEVELS REMAIN RELATIVELY DRY KEEPING THE RAIN CHANCES SLIGHT.
SKIES WILL CLEAR BEHIND THIS SYSTEM AND TEMPERATURES WILL REMAIN
COOL THROUGH THE WEEKEND. LOOKING AT MODELS LOW LEVEL TEMPERATURE
FIELDS... WILL KEEP FORECAST TEMPERATURES ON THE COOL SIDE OF
GUIDANCE RANGE AND GENERALLY BELOW MAV NUMBERS TONIGHT THROUGH
FRIDAY NIGHT.

THERE ARE SOME SPECIFIC MODEL DIFFERENCES AFFECTING FORECAST
TEMPERATURES EARLY NEXT WEEK. GFS ENSEMBLE MODEL SPREAD IS
RIDICULOUS WITH LOW-LEVEL TEMPERATURES EARLY NEXT WEEK. H8
TEMPERATURES AT 00Z/WEDNESDAY HAVE A SPREAD OF 16.5 DEGREES C AT
OKC /FROM -7.5 TO +9/ AND 23 DEGREES C AT GAG /-13 TO +10/.
GFS ENSEMBLE GRIDDED SURFACE MAX TEMPERATURE FIELDS ALSO SHOW A
HEALTHY RANGE FOR TUESDAY AFTERNOON WITH VALUES FROM 26 TO 58 AT
GAGE AND 33 TO 66 AT WICHITA FALLS. SOME OF THIS DIFFERENCE IS
EXPLAINED BY JUST WHERE THE SURFACE FRONT AND THE TEMPERATURE
GRADIENT IS LOCATED AS ALMOST ALL MEMBERS /AS WELL AS ECMWF/ SHOW
COLD AIR MOVING AT LEAST INTO THE CENTRAL PLAINS... BUT THIS
SPREAD GIVES LOW CONFIDENCE IN ANY PARTICULAR SOLUTION THIS FAR
IN ADVANCE. WITH THE SIGNAL OF COLD AIR MOVING SOUTH THROUGH THE
PLAINS... WILL LOWER TEMPERATURES IN THE EXTENDED... BUT NOT
NEARLY AS LOW AS MEX MOS NUMBERS AS THE OPERATIONAL GFS IS ONE OF
THE COLDER ENSEMBLE MEMBERS. PRECIP CHANCES WILL SPREAD ACROSS THE
AREA AHEAD OF UPPER TROF THAT DEVELOPS IN THE WESTERN UNITED
STATES AND MOVES TOWARD THE PLAINS WITH BEST CHANCES CURRENTLY
LOOKING TO BE MONDAY NIGHT INTO WEDNESDAY MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  39  21  41  23 /   0   0  10   0 
HOBART OK         39  18  41  23 /  10  10   0   0 
WICHITA FALLS TX  42  23  43  26 /  10  20  20   0 
GAGE OK           37  10  40  16 /  10   0   0   0 
PONCA CITY OK     38  18  40  22 /   0   0   0   0 
DURANT OK         44  26  43  24 /   0  10  10   0 

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...FREEZE WARNING UNTIL 9 AM CST THIS MORNING FOR OKZ031-032-
     041>043-046>048-050>052.

TX...NONE.
&&

$$