FXUS63 KOAX 090310
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
910 PM CST TUE FEB 8 2011
.DISCUSSION...
MAIN CONCERN OVERNIGHT WILL BE TEMPERATURES...AND WHAT EFFECT THE
CLOUDS COULD HAVE. LIGHT SNOW ALONG THE KS/NE BORDER REGION WILL
LIKELY END BY MIDNIGHT AS IT PUSHES FURTHER SOUTH INTO
KANSAS...WITH SOME MINOR ACCUMULATIONS EXPECTED.
LATEST OBSERVATIONS ALONG AND SOUTH OF A LINE FROM COLUMBUS TO RED
OAK INDICATE CLOUD BASES 10000 FEET OR LESS...BUT CIRRUS SHIELD
EXTENDS WELL NORTH INTO SOUTH DAKOTA AND SOUTHERN MINNESOTA. THE
CLOUDS WERE HELPING TO INSULATE THE REGION...KEEPING TEMPS UP...OR
EVEN RISING A DEGREE OR TWO AFTER SUNSET. WHILE THE CLOUDS WILL
CONTINUE TO DECREASE FROM NORTH TO SOUTH...MAY HAVE TO CONSIDER
INCREASING FORECAST LOWS SOUTHERN HALF OF THE FORECAST AREA...ESPECIALLY
CONSIDERING THE SOURCE REGION OF MILDER AIR THAT REMAINS WEST OF
THE AREA. THIS THANKFULLY MAY LIMIT OUR ABILITY TO REACH WIND
CHILL ADVISORY CRITERIA OF -20 OR COLDER IN ALL BUT THE AREAS
WHERE SKIES CLEAR ACROSS NORTHEAST NEBRASKA.
OTHERWISE...NO OTHER CHANGES IN THE ONGOING FORECAST.
&&
.PREV DISCUSSION... /ISSUED 246 PM CST TUE FEB 8 2011/
SHORT TERM...TONIGHT THROUGH FRIDAY
IMMEDIATE CONCERN IS FOR ANY PRECIP POTENTIAL IN THE SOUTHERN CWA.
POTENT UPPER LEVEL STORM SYSTEM /ASSOCIATED WITH A 120 M H5 HEIGHT
FALL AT GJT AT 12Z/ IS PROGGED TO CONT EWD THRU MAINLY THE
SOUTHERN PLAINS. NEVERTHELESS...LARGE-SCALE ASCENT IS SPREADING
THRU NRN KS AND SRN NEB THIS AFTN. ATMOSPHERE IS PRETTY DRY ACRS
OUR SOUTHERN FA...BUT GIVEN THE EXPECTED PERSISTENT LIFT AND
LOWERING AFTN CIGS IN THIS AREA...FEEL IS WAS PRUDENT TO INCLUDE
SOME EVNG POPS FOR JEFF/GAGE COUNTIES...BUT KEPT ANY AMOUNTS UNDER
A HALF AN INCH. OTHERWISE ANOTHER COLD NIGHT IS IN STORE FOR
THE FA. MODELS ACTUAL BRING IN SOME WARMER SFC TMPS THIS EVNG AND
THIS SEEMS REASONABLE GIVEN UPSTREAM SFC TMPS OVER CNTRL AND WRN
NEB. THIS WILL HAVE AN EFFECT ON OVERNIGHT LOWS AND HAVE INCREASED
THESE IN MANY LOCATIONS. DESPITE THIS...WITH AN INCREASING SFC
GRADIENT OVER THE CNTRL AND ERN CWA THIS EVNG OVERNIGHT WINDS
SHLD STAY UP...AND THIS WILL LEAD TO WIND CHILL ISSUES AGAIN. WE
WILL ISSUE AND ADVISORY GENERALLY ALONG AND NORTH OF I-80
OVERNIGHT INTO WED MRNG. LITTLE IN THE WAY OF SENSIBLE WX IS THEN
EXPECTED TO ROUND OUT THE WORK WEEK. THE CWA WILL REMAIN IN NW
FLOW THRU THE SHRT TERM...BUT WITH THE ARCTIC HIGH PUSHING OFF TO
THE E...WILL SEE SOME INCREASE IN TMPS EACH DAY THRU FRI WITH
READINGS RETURNING TO NORMAL. A WEAK SHRTWV TROF IS PROGGED TO MOV
THRU THE NRN PLAINS AND INTO THE MID MS RVR VALLEY ON THURS
NIGHT...BUT THE CWA SHLD SEE LITTLE IN THE WAY OF WX FM THIS
SYSTEM AND THUS WE WILL MAINTAIN A DRY FORECAST ATTM.
BOUSTEAD
LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
TREND TOWARD WARMER TEMPERATURES STILL ON TRACK FOR THE PERIOD.
AMOUNT OF WARMING STILL SOMEWHAT QUESTIONABLE AS 00Z EURO IS MORE
GENEROUS WITH THE TEMPERATURES INITIALLY THAN THE 12Z GFS. EURO
MAINTAINS A MORE ZONAL PATTERN THAN THE GFS WHICH WOULD EXPLAIN THIS
DIFFERENCE. MODELS ALSO SHOW A DIFFERENT IDEA ON MONDAY AS EURO
BRINGS A COLD FRONT THROUGH THE REGION SUPPORTED BY A NORTHERN
STREAM WAVE WHILE GFS BUILDS A RIDGE ACROSS THE WESTERN CONUS. AS A
RESULT...EURO COOLS DOWN A BIT LATE IN THE PERIOD WHILE GFS WARMS
THINGS UP. HAVE TRENDED TEMPERATURES A BIT BELOW THE HPC GUIDANCE IN
THE EARLY PART OF THE PERIOD THEN FOLLOWED WITH THE GUIDANCE TOWARD
WARMER TEMPERATURES IN THE LATER PERIOD. STILL BETTER THAN SUBZERO
TEMPERATURES CURRENTLY ACROSS THE REGION.
FOBERT
AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
PLAN ON VFR CONDITIONS AT ALL TAF SITES THROUGH 18Z WEDNESDAY.
THERE CURRENTLY IS A LARGE SWATH OF SNOW FROM WESTERN NEBRASKA INTO
KANSAS...HOWEVER THIS WINTER STORM WILL REMAIN TO THE SOUTH OF
NEBRASKA. SITE KLNK MAY BRIEFLY EXPERIENCE CIGS DOWN TO OVC050 WITH
A FLURRY OR TWO OVERNIGHT...BUT MOSTLY EXPECT JUST MID-HIGH CLOUDS
THEN CLEARING ON WEDNESDAY. STRONG SURFACE HIGH PRESSURE AREA WILL
REMAIN IN THE PLAINS WITH LIGHT NORTH WINDS AT TAF SITES.
NIETFELD
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WIND CHILL ADVISORY UNTIL 11 AM CST WEDNESDAY FOR NEZ011-012-
015>018-030>034-042>045-050>053.
IA...WIND CHILL ADVISORY UNTIL 11 AM CST WEDNESDAY FOR IAZ043-055-056-
069-079-080-091.
&&
$$
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