FXUS63 KOAX 270936
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
336 AM CST SUN FEB 27 2011
.DISCUSSION...
THE CHANCE FOR PRECIPITATION THROUGH TONIGHT IS THE PRIMARY FORECAST
CONCERN.
UPPER LOW WAS MOVING EAST THROUGH SOUTHERN CALIFORNIA THIS
MORNING...AND WILL EVENTUALLY SWING INTO THE PLAINS AS AN OPEN WAVE
THIS EVENING. LOW PRESSURE ALONG THE LEE OF THE ROCKIES WAS BRINGING
LIGHT SOUTH WINDS AND MOIST BOUNDARY LAYER TO MUCH OF THE PLAINS
THIS MORNING. HOWEVER FREEZING DRIZZLE HAS NOT BEEN REPORTED ACROSS
THE CWA AS WAS FORECAST OVER THE LAST COUPLE OF DAYS. MAY SEE SOME
PATCHY DRIZZLE DURING THE MORNING BUT NOT ENOUGH TO CAUSE PROBLEMS.
DIFFLUENT FLOW AHEAD OF UPPER LOW/TROUGH WILL STRENGTHEN LOW
PRESSURE IN THE LEE OF THE ROCKIES. MODELS SUGGEST CIRCULATION WILL
FORM OVER SOUTHEAST COLORADO AND MOVE EAST ALONG THE KANSAS/OKLAHOMA
BORDER DURING THE AFTERNOON AND EVENING. BROAD ASCENT WITH UPPER
TROUGH WILL BRING CLOUDS AND PRECIP TO THE REGION...HOWEVER FOCUS
FOR BEST PRECIP CHANCES WILL REMAIN TO OUR SOUTH NEARER SURFACE LOW
TRACK. STILL EXPECT SHIELD OF PRECIPITATION TO EXTEND NORTH INTO
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA THIS AFTERNOON AND EVENING.
TEMPERATURES CLIMBING TOWARD 40 AND FORECAST SOUNDINGS INDICATE
LIQUID PRECIP THROUGH THE AFTERNOON DESPITE TENDENCY FOR SURFACE
FLOW TO BECOME NORTHERLY THROUGH THE DAY. A MIX OF PRECIPITATION
TYPES WILL BEGIN THIS EVENING AS COLDER LOW LEVEL AIR IS OVERRUN BY
WARMER AIR ALOFT AHEAD OF UPPER TROUGH AXIS. AS THIS TROUGH MOVES
EAST OF THE AREA AFTER MIDNIGHT...SOUNDINGS SHOW TEMPS BELOW
FREEZING THROUGHOUT ATMOSPHERE...SO SNOW THE MOST LIKELY PRECIP TYPE
THEN. WITH SPEED OF SYSTEM AND EXPECTED LOW AMOUNTS OF
PRECIPITATION...NOT ANTICIPATING PROBLEMS DUE TO ICING OR SNOWFALL.
IF SYSTEM IS SLOWER THAN MODEL FORECASTS...A LONGER PERIOD OF
FREEZING RAIN OR SLEET WILL BE POSSIBLE IN FAR SOUTHEAST NEBRASKA
AND SOUTHWEST IOWA.
MOST OF THE PRECIPITATION WILL BE EAST OF OUR AREA AFTER MIDNIGHT
TONIGHT...EVEN WHEN CONSIDERING SLOWER NAM SOLUTION. CLEARING SKIES
ARE EXPECTED MONDAY AS NORTHWEST LOW LEVEL FLOW AND HIGH PRESSURE
SETTLE OVERHEAD. GFS SHOWS A QUICK RETURN TO SOUTHERLY FLOW IN OUR
WESTERN CWA DURING THE AFTERNOON...THUS ITS WARMER TEMPERATURE
FORECAST. HAVE LEANED THIS WAY FOR HIGHS MONDAY WITH PLENTY OF
SUNSHINE HELPING WARMUP.
UPPER FLOW IS RELATIVELY FLAT ON TUESDAY WITH SUNSHINE AND
SOUTHWESTERLY LOW LEVEL FLOW HELPING TO PUSH TEMPERATURES TOWARD 50.
THEN A WEAK COLD FRONT WILL DROP TEMPS BACK INTO THE 30S FOR
WEDNESDAY WITH INCREASING CLOUDS. AS THIS FRONT LIFTS BACK NORTH ON
THURSDAY...WARMER TEMPERATURES AND A SMALL CHANCE FOR RAIN WILL
RESULT.
THE FORECAST FOR NEXT WEEKEND IS STILL IN QUESTION WITH MODELS
SUGGESTING ANOTHER TROUGH WILL SWING THROUGH THE REGION BRINGING
COLDER TEMPERATURES AND AN OUTSIDE SHOT AT PRECIPITATION. WILL NOT
MAKE CHANGES TO THIS PART OF THE FORECAST NOW...BUT CURRENT NEAR
NORMAL TEMPERATURE FORECAST LOOKS IN JEOPARDY.
DERGAN
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
LOW LEVEL MOISTURE IS EXPECTED TO REMAIN ACROSS THE REGION THROUGH
MOST OF THE PERIOD RESULTING IN IFR CIGS AND VSBYS AT ALL THREE TAF
SITES THRU ABOUT 18Z. CIGS SHOULD IMPROVE TO MVFR AFTER 18Z FROM
NORTH TO SOUTH AS LOW LEVEL FLOW BECOMES NORTHERLY AND SOMEWHAT
DRIER AIR MOVES IN AS SURFACE LOW OVER THE SOUTHERN PLAINS LIFTS
NORTHEAST IN ADVANCE OF UPPER WAVE OVER THE SOUTHWEST CONUS.
FOBERT
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$