159
FXUS63 KOAX 022351
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
651 PM CDT Tue Sep 2 2025

.KEY MESSAGES...

- A few showers or a storm are possible in Knox, Cedar, and
  Antelope county this evening.

- Scattered showers and a few embedded thunderstorms will move
  across the area late tonight through Wednesday. Rainfall
  totals will be light, and it should not be an all day
  rain out.

- Unseasonably cool weather will continue into early next week,
  with a few chances for showers/storms. Friday into Saturday
  morning looks to be the coolest period.

&&

.DISCUSSION...
Issued at 214 PM CDT Tue Sep 2 2025

Tuesday afternoon finds a cold front stretching from southwest
NE through extreme northeast SD, and advancing steadily
southeast. The front is moving into an environment with up to
1500 J/kg of MLCAPE and modest northwest to southeast wind
shear, but the mid level lapse rates are unimpressive and the
sub-LFC environment is not particularly conducive to easy
updraft intensification. Additionally, by the time the front
approaches Knox county in our coverage area, daytime heating
will be waning. So with all this in mind, could see a few
storms, but potential for anything severe is quite limited and
in the far northwestern part of the forecast area.

The front continues to move through the area overnight tonight,
but without much precipitation along it. Rather, as an upper jet
streak noses into the region late tonight into mid Wednesday
over a mid level thermal gradient, expect a zone of showers and
storms supported by the frontogenesis and jet streak in
conjunction with elevated instability. Again, severe storms are
unlikely, but could see a bit of lightning and perhaps some
small hail if a stronger updraft can sustain. The better chance
for strong storms will be farther south along the surface front
as it moves out of Nebraska and into Kansas during peak heating.

Thursday morning will be chilly as surface high pressure builds
directly over eastern NE and western IA. Could see some valley
fog at that time, and most lows should be in the 40s so not
looking at frost just yet. Another northwesterly flow storm
system dives across the Northern Plains late Thursday, bringing
another cold front. This system is compact but should be strong
enough to support precipitation along the front, although with a
better focus closer to the upper low to our northeast. Strong
cold advection will make Friday the coolest day of the week and
put lows in the 40s once again on Saturday morning.

Next week the upper pattern changes with a chance for precip
late Monday followed by a strong ensemble signal for ridging and
warming by mid week transitioning toward southwesterly flow by
the end of the week. This points to warmer temperatures overall.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 650 PM CDT Tue Sep 2 2025

- North wind shift expected WED AM behind a cold front

- Potential for -SHRA and MVFR CIGs behind the front through
  early afternoon

Light southwest winds and dry conditions are forecast through
the overnight hours. Thunderstorms currently near the SD/NE
state line are forecast to dissipate prior to reaching OFK but
may result in increased high cloud coverage late this evening.

A cold front is then expected to move across the area from north
to south early Wednesday morning turning winds northerly with
increasing gustiness through the rest of the day. Current
timing in the TAFs for the wind shift is ~10Z OFK, and ~14Z
LNK/OMA giver or take an hour. A few showers may develop in the
wake of the front paired with lowering ceilings to MVFR to
potentially IFR. Opted to introduce TEMPOs for -SHRA with
associated MVFR CIGs at OFK and OMA through 17-18Z. Held off on
showers continuing later into the afternoon due to lower
confidence but it may need to be extended with later updates. In
addition, a few showers may drift as far south as LNK but opted
to keep the TAF dry for now due to expected lower coverage.

Petr

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.

&&

$$

DISCUSSION...Barjenbruch
AVIATION...Petr