FXUS63 KOAX 060221 AAA
AFDOAX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
821 PM CST SAT FEB 5 2011
.UPDATE...
ADJUSTED PRECIPITATION CHANCES TONIGHT.
&&
.DISCUSSION...
PER WATER VAPOR SATELLITE IMAGERY...DUAL CENTER UPPER TROUGH
EXTENDED FM SERN SD/NWRN IA BORDER TOWARD EXTREME NWRN MO AS OF 02Z.
MOSTLY LIGHT PRECIPITATION CONTINUES ROTATING SWD ALONG THIS
TROUGH ALONG MO RIVER WITH WESTWARD EXTENT STRETCHING ABOUT 60-70
MILES WEST OF THE RIVER. THUS BASED ON THESE CURRENT TRENDS...UPPED
PRECIP CHANCES THIS EVENING AND AFTER 06Z OVER NERN 1/2 OR SO OF THE
FORECAST AREA. ALSO WITH MOIST AND RELATIVELY MILD BOUNDARY LAYER
PRESENT...PER 00Z OAX SOUNDING...EXTENDED SOME RAIN MIXTURE THE
REST OF THE EVENING HOURS SE OF KOFK. DUE TO MOVEMENT OF PCPN/UPPER
TROUGH...CUT BACK POPS FAR SOUTHERN ZONES WHERE FORCING MINIMAL...
AND JUST MENTIONED FLURRIES/SPRINKLES. ALSO MADE HRLY TEMPERATURE
ADJUSTMENT TO PUSH BACK FALL BELOW FREEZING MANY AREAS UNTIL LATER
TONIGHT. CHERMOK
&&
.PREV DISCUSSION... /ISSUED 333 PM CST SAT FEB 5 2011/
SHORT TERM...TONIGHT THRU TUESDAY
PRECIPITATION AREA OF RAIN MIXED WITH SNOW IS MOVING ACROSS EASTERN
NEBRASKA AND SOUTHWEST IOWA THIS EVENING. THIS PRECIPITATION IS
ASSOCIATED WITH A SURFACE WARM FRONT THAT EXTENDS FROM A LOW OVER
SOUTHEASTERN SOUTH DAKOTA. A COLD FRONT WILL THEN PASS THROUGH THE
AREA LATER TONIGHT. SOME POST FRONTAL SNOW IS LIKELY ALONG THE
MISSOURI RIVER VALLEY INTO WESTERN IOWA. SNOW AMOUNTS SHOULD BE
LIGHT WITH THIS SYSTEM. LIGHT SNOW IS POSSIBLE ACROSS 3MUCH OF THE
AREA ON SUNDAY...BUT AMOUNTS AGAIN ARE EXPECTED TO BE LIGHT.
ON SUNDAY NIGHT INTO MONDAY MORNING...ONLY FLURRIES ARE POSSIBLE.
NEXT STORM SYSTEM WILL MOVE OUT OF MONTANA INTO COLORADO AND WYOMING
BY MONDAY AFTERNOON AND NIGHT. ISENTROPIC LIFT NORTHEAST OF THE
SURFACE LOW AND BAROCLINIC ZONE WILL PRODUCE A CHANCE OF SNOW
STARTING OVER WESTERN PARTS OF THE WARNING AREA MONDAY AFTERNOON AND
SHIFT SOUTHEAST MONDAY NIGHT INTO TUESDAY MORNING.
TEMPERATURES WILL BE IN THE 30S ON SUNDAY AND THEN BE COLDER WITH
HIGHS IN THE TEENS AND 20S ON MONDAY...AND ONLY SINGLE DIGITS FOR
HIGHS ON TUESDAY.
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY.
VERY COLD TEMPERATURES WILL CONTINUE THE FIRST PART OF THIS PERIOD.
500 MB RIDGE WILL BE IN PLACE AT THE START OF THIS PERIOD ALONG
125-140 WEST FROM THE EASTERN PACIFIC INTO ALASKA AND THE YUKON
TERRITORY. THE GFS AND ECMWF WERE IN DECENT AGREEMENT THAT THE
PATTERN WILL BE PROGRESSIVE...WITH THE RIDGE BUILDING ACROSS THE
WESTERN U.S. THROUGH LATE IN THE WEEK. A 500 MB TROUGH WILL BE
DIGGING JUST OFF THE WEST COAST OF THE U.S. BY SATURDAY...WITH
FAIRLY ZONAL FLOW IN OUR AREA.
THE RESULT WILL BE MODERATING TEMPERATURES. HIGHS WEDNESDAY ARE
EXPECTED TO BE FROM 10 TO 15...AFTER LOWS AROUND OR BELOW ZERO.
BY FRIDAY HIGHS SHOULD REACH THE 30 TO 35 IN EASTERN NEBRASKA AND
THE UPPER 20S IN SOUTHWEST IOWA. THEN HIGHS SATURDAY SHOULD BE
AROUND 5 TO 8 DEGREES WARMER THAN THOSE FRIDAY.
CONTINUED A LOW CHANCE FOR LIGHT SNOW ACROSS THE SOUTHERN PARTS
OF SOUTHEAST NEBRASKA FOR TUESDAY NIGHT...BUT THE REST OF THE
FORECAST PERIOD SHOULD BE MAINLY DRY.
SHORT TERM...TONIGHT THRU MONDAY.SHORT TERM...TONIGHT THRU
MONDAY.SHORT TERM...TONIGHT THRU MONDAY
AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
LOW PRESSURE WILL TRACK ACROSS EASTERN NEBRASKA AND WESTERN IOWA
OVERNIGHT...REACHING NORTHEASTERN MISSOURI BY SUNDAY MORNING. THE
LATEST MODEL INFORMATION INDICATES THE AIRMASS ACCOMPANYING THIS
FEATURE WILL REMAIN SATURATED THROUGH 5000 FEET WITH CEILINGS
HOVERING AROUND THE IFR/MVFR MARK. EXPECT THESE FLIGHT RESTRICTIONS
TO CONTINUE THROUGHOUT THIS TAF PERIOD. LIGHT RAIN AND SNOW WILL
CONTINUE THROUGH TOMORROW AFTERNOON...EXPECT VISIBILITIES TO BE
REDUCED TO 4 OR 5 MILES AT TIMES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SMITH/MILLER/PEARSON