FXUS63 KOAX 090911
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
311 AM CST WED DEC 9 2009
.DISCUSSION...
TAIL END OF WINTER STORM SYSTEM IS STILL AFFECTING THE CWA WITH
40+MPH WIND GUSTS...LIGHT SNOW...AND BLOWING AND DRIFTING
SNOW...WITH WIDESPREAD REDUCED VISIBILITIES. HEAVIER SNOW HAS
MOVED AWAY TO THE EAST...WITH SFC LOW AT 08Z OF AROUND 982MB
CENTERED NEAR KVYS IN N CNTRL IL. STRONGEST PRESSURE RISES OF
AROUND 4.5MB/3HR WERE CENTERED IN NERN KS. SUBJECTIVE 00Z UPPER
AIR ANALYSIS INDICATED BROAD UPPER TROUGH DIGGING INTO THE CNTRL
US...WITH EMBEDDED NEGATIVELY TILTED TROUGH FROM WRN NEB INTO
CNTRL KS...AND ANOTHER WAVE IN NRN MT. STRONGEST 500MB HT FALLS
/AROUND 160M/ WERE NOTED IN KS/OK. UPPER-LEVEL JET AROUND THE BASE
OF THE TROUGH WAS AS STRONG AS 135KT. LOWER-LEVEL WINDS WERE
STRONG IN THE AREA...WITH 08Z PROFILERS INDICATING 50KT AT 925MB
AT FBY AND WIDESPREAD 40+KT ACROSS THE CNTRL PLAINS.
MAIN FORECAST CONCERN IS WITH WEATHER CONDITIONS TODAY...ESPECIALLY
THIS MORNING. WINDS ARE CREATING SIGNIFICANT BLOWING/DRIFTING SNOW
ACROSS THE AREA. VISIBILITIES ARE NOT REACHING 1/4 MI AT OB
SITES...BUT GROUND REPORTS INDICATE VERY LOW VIS OF 1/4MI OR LESS.
WILL CONTINUE BLIZZARD WARNING THROUGH 18Z...AND ALLOW DAY SHIFT TO
EVALUATE WHETHER A WINTER WEATHER ADVISORY FOR BLOWING SNOW MAY BE
NEEDED THIS AFTERNOON. WIND SPEEDS WILL DECREASE AS PRESSURE
GRADIENT RELAXES AND HIGHEST PRESSURE RISES PASS TO THE E...BUT WIND
SPEEDS COULD STILL BE HIGH ENOUGH TO CREATE REDUCED VISIBILITIES AND
DRIFTING OVER ROADWAYS FOR MUCH OF TODAY...ESPECIALLY IN OPEN
AREAS. EXPECT VERY LITTLE IF ANY NEW SNOW ACCUMULATION AFTER
12Z...AS SUBSIDENCE BUILDS IN QUICKLY THIS MRNG. CLOUDS EXTEND FAR
UPSTREAM...AND HAVE INCREASED CLOUDS FOR TODAY...WITH A QUICK
CLEARING IN THE EVNG. EXPECT LITTLE IF ANY TEMPERATURE RISE WITH
STRONG NWLY WINDS AND COLD AIR ADVECTION.
TONIGHT...WINDS ARE EXPECTED TO DECREASE TO AROUND 5-15KT...AND AS
SKIES CLEAR...TEMPS ARE PROGGED TO FALL WELL INTO THE SINGLE DIGITS
BELOW ZERO. COMBINATION WOULD PRODUCE WIND CHILLS BELOW
-20C...WHICH IS INDICATED IN CURRENT GRIDS. WILL HOLD OFF ON AN
ADVISORY TO ALLOW DAY SHIFT TO CLEAR BLIZZARD WARNING FIRST...BUT
WILL CONTINUE TO HIGHLIGHT IN THE HWO.
KEPT TEMPS ON THE COLD SIDE THURS/FRI...WITH HIGH PRESSURE SLIDING
TO THE SOUTH KEEPING WINDS LIGHT AND CONTINUED NWLY FLOW ALOFT
KEEPING COLDER AIRMASS IN PLACE. BAROCLINIC ZONE IS PROGGED TO
EXTEND FROM THE DAKOTAS THROUGH IA/IL/KY...WITH 150KT+ UPPER-LEVEL
JET FROM THE SRN PLAINS INTO THE TN RIVER VALLEY. THAT SAID...DRY
AIRMASS REMAINS IN PLACE...AND FORECAST REMAINS DRY THROUGH SATURDAY
NIGHT.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
ALTHOUGH LIGHT SNOW WILL LIKELY BE PULLING EAST OF KOMA TAF SITE IN
09/12-09/15Z TIME PD...BLOWING SNOW WILL CONTINUE TO REDUCE VSBYS AT
ALL TAF SITES THIS MORNING WITH VSBYS PROBABLY REMAINING IN IFR
CATEGORY. SFC WINDS SHOULD PEAK BEFORE 09/12Z AND GRADUALLY SUBSIDE
THROUGH THE AFTERNOON. HOWEVER...WINDS MAY REMAIN STRONG ENOUGH TO
CONTINUE SOME VSBY RESTRICTIONS INTO THE AFTERNOON AND LATER TAFS
MAY HAVE TO REFLECT THIS. CIGS SHOULD GENERALLY BE IN MVFR RANGE
WELL INTO THE AFTN...ESPECIALLY AT KOMA AND KLNK. CIGS SHOULD LIFT
ABOVE 3000 FT LATER THIS AFTN...AND CLOUDS MAY EVEN SCATTER OUT
AROUND 10/00Z. WINDS SHOULD QUICKLY SUBSIDE AFTER SUNSET TO AT OR
BELOW 10 KTS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...BLIZZARD WARNING UNTIL NOON CST TODAY FOR NEZ011-012-015>018-
030>034-042>045-050>053-065>068-078-088>093.
IA...BLIZZARD WARNING UNTIL NOON CST TODAY FOR IAZ043-055-056-069-079-
080-090-091.
&&
$$
MAYES/CHERMOK