665
FXUS63 KOAX 051717
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1117 AM CST Wed Feb 5 2025

.KEY MESSAGES...

- Freezing drizzle could lead to slick roads Wednesday morning
  into early Wednesday evening (40-60% chance). Some questions
  still remain on exact timing, but both commutes could be
  affected. The highest potential for travel impacts will be in
  southeast NE into southwest IA where a Winter Weather Advisory
  is in effect.

- There is a 20-40% chance of mainly light snow across
  northeast NE into west-central IA late Friday night and
  Saturday with a wintry mix possible across portions of
  southeast NE and southwest IA.

- Low snow chances (20-30%) return to the forecast Monday into
  Tuesday.

&&

.DISCUSSION...
Issued at 300 AM CST Wed Feb 5 2025

Early morning analysis showed shortwave energy pushing across
NE helping to induce warm air/moisture advection in KS/MO and
southern NE into southwest IA. As a result, freezing drizzle was
well underway to our south and as of 3 AM had reached as far
north as Falls City. This should continue to expand northward
today, though questions still remain regarding exact start time
at a given point and just how far northwest it will expand into
our forecast area. Model QPF remains very low and in some cases
non- existent for us and in fact, very little guidance has QPF
where the freezing drizzle is currently falling. However,
digging a little deeper and looking at soundings reveals just
enough low level saturation (1-2 km) for at least patchy
freezing drizzle for a good chunk of the area through today. So
far, a decent proxy for areas of freezing drizzle has been the
95% contour in 0-1 km relative humidity in the RAP, so tried to
use that for a starting point for precip chances through the
afternoon. Of course, plenty of other things need to be there
too, including sufficient lift, but guidance seems to be in good
agreement that we`ll have that southeast of roughly a Lincoln
to Fremont to Tekamah line. Then it`ll mainly come down to how
long freezing drizzle will last at a given location as the
moisture/lift push eastward and perhaps some above-freezing
temperatures sneak into far southeast NE and far southwest IA
this afternoon. Of course, it doesn`t take much ice to cause
problems.

All that said, highest potential for slick roads and impacts
still remains in far southeast NE into southwest IA, where
0.05-0.07" of ice accumulation is expected and a Winter Weather
Advisory remains in effect through 6 PM. Farther northwest,
currently only expect a couple hundredths of an inch, but will
need to closely monitor trends this morning for potential
expansion. Bottom line, wherever we have ice forecast, expect at
least some slick spots on untreated and elevated surfaces.
Where we have closer to that 0.05" forecast, expect more
widespread slick roads.

Precip exits this evening and will give way to a quiet day on
Thursday with surface high pressure building in. Despite
northwesterly flow for a good chunk of the day, we`ll be a bit
warmer with temperatures topping out in the upper 30s to mid 40s
as the downslope component will help us out. Expect similar
highs on Friday under southeasterly flow. Guidance also hints at
a band of light snow near the NE/SD border Friday morning as
there will be some weak low to mid- level frontogenesis in place
and a weak shortwave trough will slide through. While higher
chances still remain to our north and west, guidance has trended
slightly higher for Knox and Cedar counties, but still only
looking at maybe a 10- 20% chance. Plus, model soundings
indicate quite a bit of low level dry air that would need to be
overcome, so if we get anything, it probably wouldn`t amount to
much more than a tenth or two.

Higher precip chances will arrive late Friday night into
Saturday with a fairly similar setup to that of today. A
relatively strong shortwave trough will slide east through the
area with a frontogenesis- driven band of snow near and north of
the NE/SD border and a warm air advection/moisture transport-
driven area of precip that could clip southeast NE/southwest IA.
Still some questions on exact track of both of these precip
areas, with some potential we`re missed completely, but
consensus still suggests roughly a 20-40% chance for a good
chunk of the area, highest again in northeast NE and far
southeast NE/far southwest IA. Again, the north precip is
favored to be light snow with amounts currently favored to be 1
inch or less while the south would likely once again be
drizzle/freezing drizzle with model soundings showing a shallow
saturated layer and no in-cloud ice.

Any precip that does fall should exit Saturday afternoon as
temperatures top out mostly in the 30s to lower 40s. Sunday is
looking quiet with surface high pressure building back in and
highs in the 30s. Additional light snow chances (20-30%) arrive
sometime Monday into Tuesday as another shortwave pushes
through, but still lots of spread in exact timing and track.
That said, there`s a little higher confidence that we`ll see a
cool-down (highs in the 20s) by the early to middle parts of
next week with guidance showing larger scale troughing digging
into the western CONUS and eventually pushing into our area.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1101 AM CST Wed Feb 5 2025

MVFR to LIFR ceilings continue across the area. Patchy, light
freezing drizzles is expected to continue across much of
southeast NE and southwest IA, impacting both KOMA and KLNK,
bringing IFR to MVFR visibility. Freezing drizzle is not
expected to reach KOFK at this time. Freezing drizzle and
associated visibility restrictions will clear from west to east
between 21 and 00z. Following shortly behind, ceilings will
return to VFR from west to east from 00-04z.

A front is expected to push from north to south through the area
from 04-08Z. Ahead of the front, winds will remain out of the
south, shifting clockwise to northwesterly behind the front.
Winds are expected to gust up to 30 kts behind the front, with
the strongest winds expected at KOFK.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Winter Weather Advisory until 6 PM CST this evening for
     NEZ042>045-050>053-065>068-078-088>093.
IA...Winter Weather Advisory until 6 PM CST this evening for IAZ055-
     056-069-079-080-090-091.

&&

$$

DISCUSSION...CA
AVIATION...Wood