FXUS63 KOAX 080026
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
626 PM CST MON MAR 7 2011
.UPDATE...
PRODUCTS WERE UPDATED SINCE THE WINTER WEATHER ADVISORY WHICH WAS
IN EFFECT UNTIL 6 PM EXPIRED. NO OTHER CHANGES TO FORECAST.
&&
.DISCUSSION...
LIGHT PRECIPITATION SHOULD CONTINUE THROUGH THE EVENING. MODEL
INDICATE INCREASING POTENTIAL FOR HEAVIER AMOUNTS SPREADING INTO
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA TUESDAY AFTERNOON.
MILLER
&&
.PREV DISCUSSION... /ISSUED 316 PM CST MON MAR 7 2011/
SHORT TERM...TONIGHT THROUGH THURSDAY.
FORECAST WILL PRESENT QUITE A CHALLENGE IN THE SHORT TERM AS AREA
WILL BE BISECTED BY SIGNIFICANT TEMPERATURE GRADIENT AS STORM SYSTEM
MOVES OUT OF THE SOUTHERN PLAINS ON TUESDAY AND HEADS TOWARD
NORTHERN MISSOURI.
INVERTED TROUGH STRETCHED FROM THE OKLAHOMA PANHANDLE INTO
SOUTHEAST NEBRASKA AND NORTHWEST IOWA AT 20Z PROVIDING BOUNDARY
BETWEEN CONTRASTING AIR MASSES. SURFACE ANALYSIS AT 20Z PAINTS A
SHARP GRADIENT ACROSS DOUGLAS COUNTY AND THE OMAHA METRO AREA
WITH KFET REPORTING 32 DEGREES WHILE KMLE HAD 46 AND KOMA 43.
THIS GRADIENT IS EXPECTED TO REMAIN QUASI-STATIONARY TONIGHT INTO
TUESDAY AFTERNOON AS THE SURFACE LOW TRACKS TOWARD NORTHERN MISSOURI.
LIGHT SNOW CURRENTLY ACROSS NORTHEAST NEBRASKA IS EXPECTED TO
DIMINISH OR END FOR A TIME AS INITIAL SHORT WAVE ALONG THE KANSAS
NEBRASKA BORDER MOVES EAST AND WEAKENS. ONLY LIGHT SNOWFALL
EXPECTED OVERNIGHT BUT AS MAIN WAVE MOVES INTO THE SOUTHERN PLAINS
ON TUESDAY PRECIP WILL INCREASE AND EXPAND ACROSS THE AREA. TIME
SECTIONS INDICATE BEST VERTICAL MOTION TUESDAY AFTERNOON.
LARGE VARIATION IN SNOWFALL AND TEMPERATURES ON TUESDAY DEPENDING
ON EXACTLY WHERE BOUNDARY BECOMES ESTABLISHED. WESTERN PARTS OF
SOUTHEAST NEBRASKA ARE EXPECTED TO BE THE FIRST TO SEE SNOW MOVE
INTO THE AREA TUESDAY MORNING WITH SNOW THEN SPREADING NORTH AND
EAST TUESDAY AFTERNOON INTO TUESDAY EVENING. WINTER WEATHER
ADVISORIES WILL REPLACE EARLIER WINTER STORM WATCH AND SPREAD
ACROSS MOST OF THE AREA WITH THE SNOW DURING THE DAY.
CURRENT INDICATIONS ARE FOR A 4 TO 6 INCH BAND OF SNOW TO STRETCH
ACROSS PARTS OF SOUTHEAST AND EAST CENTRAL NEBRASKA INTO WEST
CENTRAL IOWA WITH 1 TO 3 INCH TOTALS EITHER SIDE OF THE BAND.
TEMPERATURES WILL HAVE A BIG IMPACT ON SNOW TOTALS WITH MOST AREAS
EXPECTED TO SEE TEMPERATURES CLIMB INTO THE 30S AS THE LOW LIFTS
TOWARD MISSOURI TUESDAY AFTERNOON AND TUESDAY EVENING. MAIN
ACCUMULATING SNOW EXPECTED TO END LATE TUESDAY NIGHT AS SURFACE
LOW AND UPPER WAVE MOVE EAST OF THE AREA.
NEW SNOW COVER SHOULD HELP KEEP TEMPERATURES ON THE COLD SIDE
THROUGH THURSDAY WITH TREND TOWARD MOS GUIDANCE WHICH WAS PRETTY
SIMILAR BETWEEN MODELS.
FOBERT
LONG TERM...THURSDAY NIGHT THROUGH MONDAY.
WEAK CLIPPER WAVE NOW APPEARS TO BE MOVING THROUGH THE AREA ABOUT
12 HOURS EARLIER THAN PREVIOUSLY THOUGHT...AND TAKING A LITTLE BIT
MORE NORTHERN TRACK. THUS...WILL HAVE A SLIGHT CHANCE OF RAIN ON
FRIDAY...WITH A DECENT WARMUP AHEAD OF A COLD FRONT THAT WILL BE
MOVING THROUGH THE AREA. THIS WILL COOL TEMPS FOR SATURDAY BACK TO
NORMAL. THE NEXT WAVE IS FORECAST TO MOVE ACROSS THE REGION ON
SUNDAY AND WILL INTRODUCE A CHANCE OF SHOWERS THAT DAY...THAT WILL
BE SWEPT OUT OF THE REGION SUNDAY NIGHT WITH THE NEXT COLD FRONT
MOVING THROUGH.
DEWALD
AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
RATHER COMPLICATED FCST NEXT 24HRS. MAIN CONCERN IS PCPN TYPE
ASSOCIATED WITH POTENT STORM SYSTEM MOVING ACROSS THE CNTRL
PLAINS...MORE SPECIFICALLY WHERE THE RA/SN TRANSITION WILL SET UP
OVER ERN NEB. AS OF THE 20Z OBS IT APPEARS THE TRANSITION ZONE
EXTENDED FROM ABOUT KDNS TO KHJH. KOFK WILL BE WELL ENOUGH NORTH IN
THE COLD ZONE FOR SN TO PREVAIL THRU THE FCST PD. HOWEVER AT KOMA
AND KLNK...AM THINKING THAT DEMARCATION LINE WILL WILL HOLD IN PLACE
AND ANY PCPN AT KOMA/KLNK WILL BE A SN/RA MIX UP THRU ABOUT 08/01Z.
ACTIVITY THEN WILL QUICKLY SHUT OFF AT KOMA AND KLNK AND EXPECT DRY
CONDITIONS AT BOTH TERMINALS THRU 08/12Z. AT THAT TIME HAVE ADDED
PROB30 GROUP 08/12Z-0818Z FOR POSSIBLE -SN RELATED TO NEXT SYSTEM
MOVING IN. AS FOR KOFK...HAVE -SN PREVAILING THRU THE FCST.
MEANWHILE IFR/OCCAS MVFR CONDITIONS EXPECTED AT KOMA/KLNK...WITH
IFR/-SN PREVAILING AT KOMA.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER WEATHER ADVISORY FROM NOON TUESDAY TO 6 AM CST WEDNESDAY
FOR NEZ011-012-015>018-030>034-042>045-051.
WINTER WEATHER ADVISORY FROM 6 PM TUESDAY TO 6 AM CST WEDNESDAY
FOR NEZ052-053-067-068-090-092.
WINTER WEATHER ADVISORY FROM 6 AM TUESDAY TO 6 AM CST WEDNESDAY
FOR NEZ050-065-066-078-088-089.
IA...WINTER WEATHER ADVISORY FROM NOON TUESDAY TO 6 AM CST WEDNESDAY
FOR IAZ043-055.
WINTER WEATHER ADVISORY FROM 6 PM TUESDAY TO 6 AM CST WEDNESDAY
FOR IAZ056-069-079-090.
&&
$$