Winter Storm in Iowa, January 15 to 16, 2003

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
321 PM CST WED JAN 15 2003

FORECAST CHALLENGES ARE HOW MUCH SNOW WILL FALL AND THEN
TEMPERATURES.

SYNOPSIS--
BANDED SNOW IS INCREASING ON THE RADAR ALONG AND NORTH OF 41.5
LATITUDE.  MID LEVEL FORCING WILL BE MOVING SE DURING THE EVENING
HOURS.  DRY AIR LAYER PERSISTS NEAR SURFACE EXCEPT IN AREAS WITH
BEST SNOW.  BEST FORCING REMAINS AT MID LEVELS.

SHORT TERM FORECAST--
THE BIG QUESTION IS HOW MUCH ACCUMULATION.  ETA REMAINS GENEROUS
WITH QPF.  IF TAKEN AT FACE VALUE...THIS WOULD TRANSLATE TO 6-10
INCHES GIVEN A RATIO OF 12 OR 15 TO 1.  HOWEVER...DRY AIR INFLOW AT
SFC IS A MAJOR FACTOR...AND WILL SIMPLY EVAPORATE SEVERAL INCHES.
PREVIOUS FORECAST GENERALLY LOOKS GOOD...AT LEAST FOR NOW.

LATER PERIODS--SNOW SHOULD TAPER OFF QUICKLY TOWARD MORNING...SO
CURRENT DURATION OF WARNING LOOKS GOOD.  THE BIG QUESTION IS WHETHER
THE WIND WILL PICK UP ENOUGH THU MORNING TO CAUSE BLOWING PROBLEMS.
BEST PRES GRADIENT AND 850 MB WINDS REMAIN TO OUR WEST.  EXPECT TO
SEE SOME DRIFTING...BUT NOT ENOUGH WIND FOR A LOT OF BLOWING.

TEMPERATURES IN LATER PERIODS SHOULD BE HELD DOWN QUITE A BIT BY
SNOW COVER.  EXPECT ANY NEARLY CLEAR NIGHT WITH LIGHT WINDS TO
PRODUCE SUBZERO TEMPERATURES.  HOWEVER...THERE WILL BE A RAPID
SERIES OF CLIPPERS...MAKING TIMING OF WINDS AND OVERALL TEMPERATURE
TRENDS FROM ONE DAY TO THE NEXT SOMEWHAT DIFFICULT.  THU NIGHT INTO
FRI WILL OBVIOUSLY BE QUITE COLD.  FIRST CLIPPER MAY PRODUCE LIGHT
SNOW FRIDAY EVENING...WITH CLOUDS IN ADVIANCE OF SYSTEM INHIBITING
WARMING.  MIXING SHOULD KEEP TEMPS WARMER FRI NIGHT...8 TO 15 ABOVE.
BY SAT ETA AND GFS ALREADY BEGINNING TO PART WAYS...WITH ETA COLD
AND GFS FASTER WITH WARM ADVN.  STUCK CLOSE TO COLDER SOLUTION FOR
NOW.  GFS DEPICTS A ANOTHER FAIRLY COLD DAY SUN...WITH A STRONGER
CLIPPER THREATENING THE AREA SUN NIGHT.  BY THEN...TIMING AND TRACK
ARE BOTH QUITE UNCERTAIN...SO OPTED FOR LOW POPS.  KEPT THE REST OF
THE FORECAST DRY...ALTHOUGH YET ANOTHER CLIPPER WOULD CERTAINLY BE
POSSIBLE.  AGREE WITH HPC THAT A SOUTHERN SYSTEM IS LESS LIKELY TO
AFFECT US THE MIDDLE OF NEXT WEEK...BUT WE WILL PROBABLY GET ANOTHER
SLUG OF ARCTIC AIR MON OR TUE TO LAST INTO MIDWEEK.

.OMA...WINTER STORM WARNING FOR TONIGHT ALONG AND NORTHEAST OF A
LINE FROM SEWARD TO PAWNEE CITY. WINTER WEATHER ADVISORY TONIGHT
SOUTHWEST OF THIS LINE.

POLLACK

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-152300-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
515 AM CST WED JAN 15 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF EASTERN NEBRASKA
AND SOUTHWEST IOWA.

.DAY ONE...TODAY AND TONIGHT

A WINTER STORM WARNING IS IN EFFECT FOR MUCH OF THE AREA TODAY
AND TONIGHT.  A WINTER WEATHER ADVISORY IN EFFECT THIS AFTERNOON
AND TONIGHT FOR AREAS SOUTHWEST OF A FRIEND TO BEATRICE LINE.
SNOW WILL BECOME WIDESPREAD TODAY ACROSS EASTERN NEBRASKA AND
SOUTHWEST IOWA.  THE SNOW WILL BECOME HEAVY AT TIMES THIS
AFTERNOON AND TONIGHT. BY THURSDAY MORNING SNOW TOTALS OF 4
TO 8 INCHES ARE EXPECTED ACROSS MUCH OF EASTERN NEBRASKA AND
SOUTHWEST IOWA.  LOCALLY HIGHER AMOUNTS MAY OCCUR.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

ACCUMULATING SNOW WILL END EARLY THURSDAY MORNING.
HOWEVER...GUSTY NORTHERLY WINDS WILL DEVELOP THURSDAY MORNING
AND CONTINUE THROUGH THE DAY.  THIS WILL CAUSE SOME BLOWING AND
DRIFTING SNOW ACROSS THE AREA THROUGH THURSDAY EVENING.
NO SIGNIFICANT WEATHER IS EXPECTED FRIDAY THROUGH TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SNOWFALL REPORTS FROM STORM SPOTTERS WOULD BE HELPFUL TODAY
AND TONIGHT.

THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC AND CLIMATIC
INFORMATION IS AVAILABLE ON THE INTERNET AT
WWW.CRH.NOAA.GOV/OAX OR AT WEATHER.GOV (LOWER CASE)

ERVIN