670
FXUS63 KOAX 021042
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
542 AM CDT Tue Sep 2 2025

.KEY MESSAGES...

- Flooding is expected to continue today along stretches of Wahoo
  Creek and the Big Blue River.

- Areas of dense fog will linger until around 10 AM before dissipating.

- Unseasonably cool weather will continue into early next week,
  with a few chances for showers/storms.

&&

.DISCUSSION...
Issued at 318 AM CDT Tue Sep 2 2025

Early this morning through Wednesday:

Surface high pressure centered over the area early this morning is
creating conditions favorable for fog development, with several
locations already reporting visibilities of a 1/4 mile or less. As
such, a Dense Fog Advisory has been issued until 10 AM for portions
of eastern NE. An eventual expansion into southwest IA is possible
prior to sunrise if conditions warrant. The fog and clouds will
diminish this morning, with warmer afternoon temperatures in
the mid to upper 70s forecast.

A strong shortwave trough will dive south into the upper MS Valley
and upper Great Lakes tonight into Wednesday, with an associated
surface cold front moving through our area on Wednesday morning. A
couple strong storms are possible along the front in eastern SD and
southwest MN late this afternoon into tonight, with the CAMs
suggesting that activity may dissipate before reaching our area. As
such, this forecast update will indicate sub-15% PoPs through
much of tonight.

Better shower and thunderstorm chances (30-50% PoPs) will exist on
Wednesday, in tandem with the deeper frontal surge. A few strong
storms will again be possible during the peak of the diurnal heating
cycle on Wednesday afternoon, but by that time, the front is
expected to have slipped just to the south of our area. Precipitation
amounts should be light and generally less than 0.25", so no
additional flooding is expected. In addition to the rain chances,
the models indicate increasing near-ground, wildfire smoke
concentrations filtering into the area behind the front, which
could affect sensitive groups.

Highs on Wednesday will range from the mid to upper 60s in northeast
NE and west-central IA, to mid 70s along the KS and MO borders.


Thursday and Friday:

Another potent shortwave trough is forecast to move through the
northern Plains and upper Midwest on Thursday night into Friday,
with the attendant surface front traversing our area on
Thursday night. A strengthening warm advection regime ahead of
the front will support highs mainly in the 70s on Thursday, with
widely scattered showers and thunderstorms possible (15-25%
PoPs) with the passage of the front Thursday night. Surface
high pressure will build into the area on Friday, with highs in
the 60s.


Saturday through Monday:

Longwave troughing present east of the Rockies Friday morning is
forecast to deamplify over the weekend, with model guidance
indicating the movement of a lower-latitude disturbance through the
central and southern Plains on Sunday into Monday. There are model
differences in the amplitude of that feature, with some
solutions indicating increased rain chances across at least the
southern part of our area during that timeframe. This forecast
update will indicate sub-15% PoPs on Sunday, which increase to
15-30% on Monday morning.

High temperatures will remain below normal for this time of
year, with readings in the 60s to low 70s.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 542 AM CDT Tue Sep 2 2025

Satellite and surface observations indicate widespread dense
fog across much of northeast NE (including KOFK), with more
patchy fog with southeast extent toward the MO River, in the
vicinity of KOMA. KOFK has remained fairly steady at 1/4-1/2SM
overnight, and that trend is likely to continue through at least
13Z, with visibilities gradually improving over the next 2-3
hour. Visibilities have been more variable at KOMA owing to the
more patchy nature of the fog. This forecast update will lean
toward the low side of the observed range, with prevailing 1/2sm
through 13z, and then improving conditions thereafter. Low
clouds (FL035) have held in at KLNK overnight, though the cloud
edge is drifting south toward the terminal. Based on present
conditions, this forecast update will indicate prevailing VFR
conditions, with a TEMPO group for MVFR visibilities (4sm)
through 14z.

Light north winds this morning will become light southwest by
afternoon. There`s a small chance (20%) of showers tonight,
which will not be included in the forecast at this time.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Dense Fog Advisory until 10 AM CDT this morning for NEZ011-012-
     015>018-030>034-042>045-050>053.
IA...None.

&&

$$

DISCUSSION...Mead
AVIATION...Mead