FXUS63 KOAX 122104
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
304 PM CST SAT FEB 12 2011
.SHORT TERM...TONIGHT THROUGH TUESDAY.
LITTLE CHANGE TO OVERALL FORECAST TRENDS WITH TEMPERATURES STILL
THE MAIN CHALLENGE.
WEAK SURFACE TROUGH WAS LOCATED OVER EASTERN NEBRASKA AT 20Z WITH
STRONGER WEST TO NORTHWEST WINDS OVER CENTRAL AND WESTERN
NEBRASKA. DESPITE THE WEAKER WINDS EAST OF THE TROUGH...TEMPERATURES
HAVE STILL BEEN ABLE TO WARM INTO THE MID AND UPPER 40S BY EARLY
THIS AFTERNOON. EVEN WARMER TEMPERATURES EXPECTED ON SUNDAY AS
LARGE POOL OF +10C 850 TEMPERATURE SETS UP OVER THE CENTRAL
PLAINS IN ADVANCE OF NEXT COLD FRONT ASSOCIATED WITH DEEP CLIPPER
COMING OUT OF SOUTH CENTRAL CANADA TOWARD THE GREAT LAKES REGION.
LATEST MODELS SHOW COLD ADVECTION MOVING INTO THE AREA AFTER 18Z
ON SUNDAY AS WINDS SHIFT TO THE NORTHWEST. SOUTH HALF OF THE CWA
SHOULD SEE THE BEST WARMING ON SUNDAY WITH HIGHS IN THE MID 50S OR
BETTER. FURTHER NORTH...SOME POTENTIAL FOR STRONG WINDS IF
INVERSION IS NOT ABLE TO HOLD. CURRENT FORECAST SOUNDINGS MAINTAIN
THE INVERSION FOR NOW WITH 40+ KTS ABOVE 900MB.
BRIEF COOLDOWN ON MONDAY BUT WARMER AIR RETURNS MONDAY NIGHT INTO
TUESDAY. SOME LOW LEVEL MOISTURE ALSO INDICATED FOR THE FAR
SOUTHEAST TUESDAY MORNING. SOME DRIZZLE CURRENTLY IN FORECAST FOR THE
SOUTHEAST BUT HAVE TRIMMED AREA IN THIS FORECAST.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY.
VERY WARM TEMPERATURES COULD LEAD TO RIVER ICE BREAKUP IN THE
EXTENDED PERIODS AND WL LIKELY BE THE MAIN FORECAST CONCERN. AN
UPPER LEVEL RIDGE WL CONTINUE TO FLATTEN AND PUSH EAST EARLY IN THE
PERIOD AS A TROF MOVES ONTO THE WEST COAST. THIS WL LEAD TO VERY
MILD CONDITIONS THROUGH THE NEXT SIX DAYS WITH TUESDAY NIGHT BEING
ONE OF THE FIRST NIGHTS ABOVE FREEZING. AFTER SEVERAL DAYS OF ABOVE
FREEZING TEMPERATURES...ICE ON THE RIVERS SHOULD BE ABLE TO BREAK UP
AND OUR SNOWPACK SHOULD QUICKLY MELT AWAY. HOW THIS WILL ALL PLAY
OUT AND IF/WHERE THERE COULD BE ANY ICE JAMS ON THE RIVERS IS
IMPOSSIBLE TO FORECAST AT THIS POINT...BUT SOMETHING PEOPLE WITH
INTERESTS ALONG THE PLATTE AND ELKHORN RIVERS SHOULD BE AWARE OF FOR
THE NEXT COMING WEEK. FOR NOW WILL HIGHLIGHT IN THE LATEST HWO.
SOUTHWESTERN TROF WL MOVE A PIECE OF ENERGY ACROSS THE WESTERN CONUS
LATE IN THE WEEK AND A SFC CYCLONE WILL DEVELOP ACROSS THE NRN HIGH
PLAINS REGION...PUSHING INTO THE NRN PLAINS BY LATE THURSDAY.
FORECAST AREA WILL REMAIN ON THE WARM SIDE OF THIS FEATURE FOR A
BRIEF WHILE UNTIL THE BROAD UPPER TROF BEGINS TO DIG FURTHER SOUTH
INTO THE CNTRL CONUS BRINGING COLD CANADIAN AIR DOWN WITH IT. STRONG
COLD FRONT WILL DROP DOWN LATE IN THE PERIOD WITH HIGHS ON SATURDAY
POSSIBLY DIPPING BELOW FREEZING ONCE AGAIN. WL LEAVE THIS TIME
PERIOD DRY FOR NOW AS MAIN ENERGY IS EXPECTED TO REMAIN EITHER TO
OUR FAR NORTH OR OUR FAR SOUTH AT THIS POINT.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
VFR CONDITIONS SHOULD CONTINUE THROUGH FORECAST PERIOD WITH MAINLY
JUST CIRRUS CLOUDS EXPECTED. VERY STEEP INVERSION EVIDENT ON KOAX
12/12Z SOUNDING SEPARATED A SSW SURFACE WIND AROUND 10KTS FROM
WESTERLY WINDS OF 30KTS 1-2K FEET AGL...WITH SIMILAR TYPE LOW LVL
WINDS FORECAST INTO SUNDAY. THUS...LOW LVL WIND SHEAR WAS MENTIONED
IN KOFK/KOMA TAFS WHERE LESS MIXING OCCURRED THROUGH 12/19Z. PATCHY
FOG COULD DEVELOP BY SUNDAY MORNING...BUT WITH THE MODERATE WINDS
EXPECTED ABOVE THE SFC AND THICKER CIRRUS SPREADING OVERHEAD...FELT
COVERAGE OR LIKELIHOOD NOT HIGH ENOUGH TO INCLUDE IN 18Z TAFS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
FOBERT/KERN/CHERMOK