FXUS63 KOAX 170945
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
345 AM CST THU FEB 17 2011
.DISCUSSION...
INITIAL CONCERNS WILL BE EROSION OF DENSE FOG...THEN RECORD OR
NEAR RECORD TEMPERATURES TODAY...AND TEMPERATURES THROUGH FRIDAY
NIGHT. LONGER TERM CONCERNS WILL BE PRECIPITATION POTENTIAL AND
PRECIPITATION TYPE SATURDAY THROUGH MONDAY.
LOW CLOUDS AND FOG THAT HELD TEMPERATURES DOWN ACROSS PARTS OF
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA WEDNESDAY...MOVED NORTH
OVERNIGHT. THE SURFACE WARM FRONT HAD LIFTED NORTH OF TEKAMAH AND
DENISON IOWA. THE TEMPERATURES HAD RESPONDED AT DENISON AT 50
DEGREES WITH A SOUTH WIND GUSTING TO 21 KTS...HOWEVER TEKAMAH WAS
37 WITH ZERO VISIBILITY AND JUST A LIGHT SOUTH WIND. TRIMMED BACK
THE DENSE FOG ADVISORY WITH IMPROVEMENT IN THE VISIBILITIES
OVERNIGHT AT NEBRASKA CITY/OMAHA/RED OAK. THROUGH THE EARLY MORNING
HOURS...THE WINDS IN PARTS OF NORTHEAST NEBRASKA AND EAST CENTRAL
NEBRASKA WILL NOT BE AS STRONG AS SOUTHWEST IOWA...SO AT RISK FOR
LINGERING FOG. LEFT AREAS FROM TEKAMAH NORTHEASTWARD IN THE
ADVISORY UNTIL THESE LOW CLOUDS CAN GET SCOURED OUT.
THE H850 THERMAL RIDGE IS OVER THE FORECAST AREA NOW...HOWEVER BY
18Z WILL HAVE SHIFTED EAST OF THE AREA...WITH SIGNIFICANT COOLING
BEGINNING TO MOVE IN BEHIND THE COLD FRONT. MIXING OF THESE WARM
TEMPERATURES ALOFT WILL BE MAXIMIZED OVER THE SOUTHERN HAVE OF THE
FORECAST AREA...THUS FORECASTED HIGHS WILL BE A CHALLENGE TODAY.
COOLED TEMPERATURES IN TO NORTH TO THE 50S...AND LEFT RECORD OR
NEAR RECORD TEMPERATURES FARTHER SOUTH IN THE 60S TO LOWER 70S.
THE RECORD FOR OMA/LNK/OFK ARE 69/72/72 RESPECTIVELY. REINFORCING
COLD AIR IS ON TAP TONIGHT AS SURFACE HIGH PRESSURE BUILDS IN.
ALREADY BY SATURDAY THE SOUTH FLOW RETURNS AND A STRENGTHENING LOW
LEVEL JET AND ISENTROPIC LIFT MAY PRODUCE SOME LIGHT RAIN BY
SATURDAY AFTERNOON TOWARD FALLS CITY.
SATURDAY NIGHT...DEVELOPING LOW PRESSURE OVER EASTERN COLORADO
MOVES INTO KANSAS WITH STRONG SOUTH FLOW PROVIDING LIFT OVER A
WARM FRONT IN KANSAS. ACROSS THE SOUTH THE PRECIPITATION SHOULD
MAINLY BE RAIN...HOWEVER FARTHER NORTH IN THE COLDER AIR THERE
WILL BE A TRANSITION/MIX OF FREEZING RAIN...SLEET...AND SNOW.
THERE IS STILL DISAGREEMENT ON THE TRACK AND STRENGTH OF THE
SYSTEM. WILL MAKE SOME INITIAL ADJUSTMENT FOR THE COLD AIR
SUNDAY...SO WILL TREND TEMPS DOWNWARD AND PRECIP TYPE COLDER WITH
MIX OF PRECIP.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
WITH THE WARM FRONT MOVG N OF THE TERMINALS THIS MRNG...OTHER THAN
SOME MORNING MVFR VISBY DUE TO HZ...VFR CONDS ARE EXPECTED THRU THE
PERIOD. WL LIKELY SEE SOME GUSTS IN THE SFC WINDS THIS AFTN AS THEY
BECOME SW. THEN A CDFNT WL MAKE ITS WAY THRU THE TERMINALS THRU THE
AFTN WITH WINDS BECOMING NW THIS EVNG AT ALL LOCATIONS. FNT WL BE
DRY THOUGH WITH JUST SOME MID AND HIGH LVL CLDS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...DENSE FOG ADVISORY UNTIL 8 AM CST THIS MORNING FOR NEZ015-033-
034.
IA...DENSE FOG ADVISORY UNTIL 8 AM CST THIS MORNING FOR IAZ043.
&&
$$
ZAPOTOCNY/BOUSTEAD