773 
FXUS63 KOAX 052100
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
300 PM CST SAT JAN 5 2013

.SHORT TERM...TONIGHT THROUGH TUESDAY.

LITTLE CHANGE TO CURRENT TRENDS IN THE SHORT TERM WITH
TEMPERATURES STILL THE PRIMARY CONCERN IN THE FORECAST.

COLD FRONT MOVING THROUGH THE AREA THIS AFTERNOON WITH GUSTY
NORTHWEST WINDS FOUND BEHIND THE FRONT OVER NORTHEAST NEBRASKA AT
20Z. WINDS ARE EXPECTED TO GRADUALLY DIMINISH ACROSS THE AREA THIS
EVENING AS THE FRONT MOVES QUICKLY SOUTHEAST REACHING THE LOWER
OHIO VALLEY BY SUNDAY MORNING. UPPER RIDGE MOVES OVER THE REGION
ON SUNDAY BUT WINDS ARE EXPECTED TO BE ON THE LIGHT SIDE FOR MUCH
OF THE DAY WHICH WILL LIMIT MIXING AND BETTER WARMING. AREA LOOKS
TO REMAIN BETWEEN NORTHERN AND SOUTHERN STREAM FEATURES MONDAY
INTO TUESDAY WITH DAYTIME HIGHS EXPECTED TO BE ABOVE SEASONAL
NORMALS.

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY.

MAIN FORECAST ISSUE IN THE EXTENDED CONTINUES TO BE WED 
NIGHT/THURSDAY SYSTEM...ALTHOUGH A POTENTIAL DAY 7 STORM LOOMS PER 
12Z GFS AS WELL.  FOR THE FIRST SYSTEM...12Z DETERMINISTIC ECMWF 
CONTINUED TO LIFT UPPER SYSTEM ACROSS FORECAST AREA 
THURSDAY...ALTHOUGH A LITTLE SLOWER THAN PRIOR RUNS.  ALTHOUGH GFS 
CONTINUED DRY...MORE OF ITS ENSEMBLE MEMBERS WERE FOLLOWING ECMWF 
LEADING GFS MEAN TO BE MORE PRECIP BULLISH WITH 12Z SUPPORT FROM NOW 
FROM LATEST CANADIAN.  BASED ON 12Z MODEL TRENDS LOWERED POPS WED 
NGT AND RESTRICTING THEM TO FAR SOUTH...AND INCREASED SLIGHTLY ON 
THU FROM A MODEL/PREV FCST BLEND.  WOULD SUSPECT IF OPERATIONAL GFS 
CONTINUES SHIFTING TOWARD ECMWF AND THE LATTER MODEL REMAINS 
CONSISTENT...POPS WOULD NEED FURTHER INCREASING IN LATER FORECASTS.  
ONE THING MODELS DO AGREE ON IS PRECIP TYPE WOULD PROBABLY NOT BE 
SNOW.  FORECAST SOUNDINGS AND THERMAL/THICKNESS FIELDS RIDGING FROM 
SE TO NW ACROSS THE FORECAST AREA...COINCIDENTAL TO EXPANDING
PRECIP...WOULD POINT TO MAINLY RAIN. WILD CARD WOULD BE INITIAL
EVAPORATIVE COOLING POSSIBLY LEADING TO A BRIEF PERIOD OF FREEZING
RAIN. HOWEVER...BELIEVE TIMING OF PRECIP WILL BE SUCH THAT IT
ARRIVES AS SFC TEMPS/DWPTS CLIMB ABOVE FREEZING. ALTHOUGH
CONFIDENCE IN SKILL OF HOURLY FORECASTING THAT FAR OUT NOT THE
HIGHEST...MADE SOME HOURLY ADJUSTMENTS TO ACCOUNT FOR THAT. ALSO
INCREASED TEMPS A BIT WED/THU...ESPECIALLY SERN ZONES WHERE
EXISTING SNOW COVER IS DWINDLING.

WITH SOME TIMING DIFFERENCES BETWEEN FASTER GFS AND SLOWER ECMWF 
OPTED TO NOT MAKE CHANGES TO THE DRY FORECAST THU NGT THAT A MODEL 
BLEND PRODUCED. ALSO FELT MOST OF THE AREA WOULD BE DRY ON FRIDAY AT 
LEAST BEFORE NEXT SYSTEM APPROACHES.  SINCE 12Z ECMWF WOULD APPEAR 
TO LIFT MOST OF THE ENERGY WITH THIS NEXT SYSTEM BEYOND DAY 
7...LOWERED PRECIP CHCS NEXT SATURDAY DOWN A BIT FROM HIGH CHANCE 
CATEGORY THIS SET OF MODELS...ESPECIALLY GFS...WOULD SUGGEST.


&&

.AVIATION...
18Z TAFS FOR KOMA...KLNK...KOFK. 

CLEAR SKIES TODAY WILL GIVE WAY TO MVFR LOW CLOUDS THIS EVENING AND 
PORTIONS OF THE OVERNIGHT HOURS. THIS LOW LEVEL MOISTURE WILL ALSO 
BE ACCOMPANIED BY STRONGER WINDS. NOT ENTIRELY SURE IF THESE WINDS 
WILL MIX DOWN TO THE SURFACE...IF NOT EXPECT WINDS UP TO 40 KNOTS 
AROUND 2000 FEET. BOTH THE LOW CLOUDS AND STRONGER WINDS WILL 
DIMINISH AFTER 06Z AT ALL TAF SITES.

&&

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

$$

FOBERT/CHERMOK/PEARSON