FXUS63 KOAX 062156
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
356 PM CST SUN MAR 6 2011
.SHORT TERM...TONIGHT THROUGH WEDNESDAY.
CURRENT HEADLINES IN GOOD SHAPE REGARDING POTENTIALLY SIGNIFICANT
WINTER STORM LOOMING ON THE HORIZON MID WEEK. DETERIORATING WEATHER
CONDITIONS START TONIGHT AND SPREAD WEST TO EAST IN RELATION TO
INCREASING UPPER SUPPORT SEVERAL FROM SEVERAL MINOR IMPULSES
MOVING THRU...COUPLED WITH STRONG 290K SFC UPGLIDE ALONG LOW/MID
LYR AGEOSTROPHIC FORCING. WILL FOCUS POPS ON THE WRN PERIPHERY
WHERE DYNAMICS WILL BE PREVALENT. PCPN TYPE WILL BE AN ISSUE
TONIGHT DURING THE EVENING HOURS WITH A MIX OF FREEZING/FROZEN
MAINLY FOR AREAS ALONG AND SOUTH OF THE I-80 CORRIDOR. AS A MATTER
OF FACT...MODELS ADVERTISING PCPN OVER MOST OF SOUTHEAST NEB AND
SOUTHWEST IOWA PCPN WILL LIKELY ALTERNATE MONDAY AFTN THRU TUESDAY
NIGHT...RAIN DURING THE DAY AND RAIN/SNOW MIX OVERNIGHT. MEANWHILE
AREAS JUST TO THE NORTH OF I-80 ARE ON TRACK TO SEE SIGNIFICANT
SNOWFALL ACCUMULATIONS WITH THE ONSET OF THIS WINTER EVENT. AT THE
MOMENT...AM ANTICIPATING THE AXIS FOR HEAVIEST ACCUMULATIONS TO
GENERALLY BE FROM ABOUT MONONA COUNTY IN WEST CNTRL IA TO SEWARD
WITH GENERALLY 7 TO 10 INCHES TOTAL BY EVENTS END WEDNESDAY
MORNING. LOCATION IS PRIME FOR HEAVY SNOW GIVEN FAVORABLE
FACTORS...-2C TO -8C 850MB TEMPS...INCREASING DENDRITIC FORCING
WRAPPING AROUND LIFTING SFC LOW...TRACK OF 500MB HFC ERN KS-NRN
MO. NOTE...CONFIDENCE LEVEL WHERE SNOW AXIS WILL EVENTUALLY SET UP
IS LOW AT THIS POINT GIVEN ACTIVITY IS A FEW DAYS OUT. THERMAL
BOUNDARY DELINEATING THE RAIN/SNOW LINE COULD VERY WELL SHIFT WITH
UPCOMING MODEL RUNS.
DEE
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY.
STILL A RELATIVELY QUIET PERIOD AS A WEAK RIDGE PREVAILS EARLY IN THE
PERIOD. THERE IS A WEAK CLIPPER SYSTEM STILL PROGGED TO MOVE DOWN THE
MISSOURI RIVER VALLEY FRIDAY NIGHT. THIS FEATURE HAS BEEN CONSISTENT
OVER THE LAST COUPLE OF DAYS AMONG MEDIUM RANGE MODELS...WHICH DRIVES
A COLD FRONT THROUGH THE AREA. INITIALLY WAS CONCERNED ABOUT
AVAILABILITY OF MOISTURE YESTERDAY...BUT THERE APPEARS TO BE A NARROW
WINDOW FOR A CHANCE OF RAIN CHANGING TO SNOW FRIDAY NIGHT...BUT
ENDING BY DAYBREAK SATURDAY. SUCH A QUICK MOVING SYSTEM THAT THE
OVERALL IMPACT WOULD BE MINIMAL.
WALDO
&&
.AVIATION...
18Z TAFS
VFR CONDITIONS WILL CONTINUE AT KOFK/KOMA/KLNK THROUGH 08-12Z
MONDAY. FAST MOVING STORM SYSTEM WILL MOVE ACROSS THE AREA LATE
TONIGHT INTO MONDAY. BETWEEN 08-12Z...CEILINGS WILL DECREASE TO
MVFR CONDITIONS AND THEN 2-3 HOURS LATER TO IFR CONDITIONS WITH SNOW
AND FOG. IFR CONDITIONS WILL THEN CONTINUE THROUGH 18Z MONDAY.
SMITH
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...WINTER STORM WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY
NIGHT FOR NEZ015-018-032>034-044-045-051.
WINTER STORM WATCH FROM LATE MONDAY NIGHT THROUGH LATE TUESDAY
NIGHT FOR NEZ016-017-030-031-042-043-050-065.
IA...WINTER STORM WATCH FROM TUESDAY MORNING THROUGH LATE TUESDAY
NIGHT FOR IAZ043.
&&
$$