000
FXUS63 KOAX 052318
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
518 PM CST WED MAR 5 2014

.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 326 PM CST WED MAR 5 2014

SHORTWAVE TROUGH AND ASSOCIATED AREA OF MID-LEVEL FRONTOGENESIS
THAT BROUGHT THE LIGHT SNOW TO SOUTHEAST NEB TODAY WILL CONTINUE
TO PUSH SOUTHEAST OF THE AREA THROUGH THE REST OF THE AFTERNOON.
20Z SURFACE ANALYSIS INDICATED A RIDGE AXIS FROM CENTRAL NEB INTO
SW MN. MODELS ARE CONSISTENT IN DEVELOPING THIS ACROSS THE FA
OVERNIGHT WITH THIS AXIS FROM ERN KS INTO IA BY THU MORNING. LOW-
LEVEL FLOW CURRENTLY FROM THE NE WILL BECOME LIGHT...BUT ALSO
VEER IN TIME TO THE SOUTHEAST. LATEST SURFACE OBSERVATIONS FROM IA
INDICATE SOME AREAS OF LOWER CLOUDS TO THE EAST...AND AT LEAST
SOME SHORT TERM MODEL GUIDANCE SUCH AS THE RAP/HRRR WOULD DEVELOP
THIS LOW CLOUDS WEST THIS EVENING AND EXPAND ACROSS A GOOD PART OF
THE FA OVERNIGHT. THIS SCENARIO ISN`T OUT OF THE QUESTION GIVEN
THE SYNOPTIC PATTERN AND WE HAVE INCREASED OVERNIGHT LOWS IN CASE
THIS DOES PAN OUT. ANY REMAINING CLOUDS ON THU MORNING SHOULD
QUICKLY DISSIPATE OR PUSH NORTHEAST OF THE AREAS AS THE PRESSURE
GRADIENT INCREASES AND SOUTHWEST WINDS DEVELOP. GIVEN THE 925 MB
TEMPERATURES AND SUN EXPECTED WE SHOULD SEE HIGHS PUSH INTO THE
50S WEST TO 40S EAST.

THE NEXT SHORTWAVE TROUGH WILL ADVANCE INTO THE NORTHERN PLAINS ON
THURSDAY NIGHT BRINGING A COLD FRONT TO NEAR THE SD/NEB BORDER BY
12Z FRI. AHEAD OF THE FRONT WE SHOULD SEE A FAIRLY MILD NIGHT
WITH SOUTH WINDS AND INCREASING HIGH CLOUDS. THE FRONT WILL PUSH
SOUTH THROUGH THE FA ON FRIDAY WITH TEMPERATURES IN THE CENTRAL
AND NORTHERN CWA FALLING DURING THE AFTERNOON. WE STILL EXPECT
HIGHS INTO THE UPPER 40S IN THE SOUTH THOUGH WITH THE FRONT NOT
ARRIVING UNTIL THE AFTERNOON. ALL MODELS INDICATE AT LEAST
MARGINAL LARGE-SCALE SUPPORT FOR ASCENT DURING THE DAY ON FRIDAY
AS THE POSITIVELY-TILTED UPPER LEVEL TROUGH MOVES THROUGH THE
AREA. THE MODELS HAVE VARYING SOLUTIONS THOUGH AS TO THE STRENGTH
AND PLACEMENT OF THE FRONTOGENESIS. THE NAM/GEM ARE THE STRONGEST
WITH THE MID-LEVEL FRONTAL BAND WHILE THE GFS/EC ARE WEAKER.
CURRENTLY WE PREFER THE WEAKER SOLUTIONS TO THE FRONTAL
CIRCULATION GIVEN THE GENERALLY WEAK LARGE-SCALE SUPPORT FOR
ASCENT...BUT THE NAM/GEM CAN`T TOTALLY BE RULED OUT GIVEN THE
WEAK STATIC STABILITY AND DECENT MID-LEVEL MOISTURE WITH SPECIFIC
HUMIDITY OF 3 G/KM AROUND 750 MB. GIVEN THE VARYING SOLUTIONS WE
INCREASED POPS FOR FRIDAY...STARTING IN THE NORTH IN THE
MORNING...SINKING SOUTHWARD THROUGH THE DAY...BUT ONLY TO MID
CHANCE RANGE AT THIS TIME. POINT FORECAST SOUNDINGS AND CROSS
SECTIONS INDICATE PRECIP WOULD LIKELY START AS A RA/SN MIX
TRANSITIONING TO SN AS THE COLDER AIR MOVES IN. WE WILL REMAIN
CONSERVATIVE ON SN AMOUNTS THOUGH GIVEN THE VARYING MODEL
SOLUTIONS. THIS SYSTEM MOVES OUT OF THE AREA BY SAT MORNING WITH
THE SURFACE HIGH PUSHING IN AND MUCH COOLER AIR TO START THE
WEEKEND.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 326 PM CST WED MAR 5 2014

PERIOD WILL BEGIN WITH NORTHWEST FLOW ALOFT WITH THE FLOW BECOMING
ZONAL BY EARLY IN THE WORK/SCHOOL WEEK. DRY WEATHER IS EXPECTED
THROUGH MUCH OF THE TIME PERIOD WITH MUCH WARMER TEMPERATURES MOVING
IN SUNDAY AND MONDAY WHEN WE APPROACH 60...WITH NEAR NORMAL
TEMPERATURES ON TUESDAY AND WEDNESDAY IN THE 40S. THE ECMWF DEVELOPS
A SHARP SHORTWAVE TROUGH AND DIGS IT ACROSS THE REGION ON WEDNESDAY
WHEREAS THE GFS DRAGS THIS FEATURE ACROSS THE NORTHERN PLAINS...
KEEPING OUR AREA DRY. WILL CONTINUE TO MONITOR THIS CLOSELY BUT WILL
KEEP THE FORECAST DRY FOR NOW. COOLER TEMPS WILL BE DRAWN SOUTH
BEHIND THIS FEATURE.

&&

.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 514 PM CST WED MAR 5 2014

TRICKY CLOUD FORECAST OVERNIGHT WITH LOW CONFIDENCE IN EVOLUTION
OF LOWER MVFR CLOUDS THAT WERE JUST EAST OF THE TAF SITES AT 23Z.
EASTERLY LOW LEVEL FLOW COULD ALLOW THESE CLOUDS TO BACKBUILD TO
THE WEST...ESPECIALLY AT KOMA WHERE THEY COULD MOVE BACK IN
THROUGH THE EVENING. LOW LEVEL FLOW DOES TURN SOUTHERLY AND
INCREASE THROUGH THE NIGHT...WHICH MAY PREVENT THIS MOISTURE FROM
MAKING IT AS FAR WEST AS KLNK/KOFK. IF CLOUDS DO MOVE BACK INTO
KOMA...BELIEVE THEY MAY SCATTER BACK OUT BY 09-13Z. SOUTHERLY
WINDS THEN INCREASE TO 12 KNOTS OR GREATER BY 13-15Z...WITH GUSTS
INTO THE LOWER TO MID 20 KNOT RANGE BY 16-18Z THAT SHOULD CONTINUE
UNTIL THE END OF THE PERIOD.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$

SHORT TERM...BOUSTEAD
LONG TERM...KERN
AVIATION...DEWALD