775
FXUS63 KOAX 291041
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
541 AM CDT Fri Aug 29 2025

.KEY MESSAGES...

- Patchy fog this morning.

- Seasonably cool weather will continue.

- Rain chances increase in northeast Nebraska this afternoon
  into tonight (peak PoPs of 30-50% tonight).

- Rain chances become more widespread Saturday into Sunday night
  (peak PoPs increasing to 50-75%), with locally heavy rainfall
  possible. Severe weather is not expected.

&&

.DISCUSSION...
Issued at 332 AM CDT Fri Aug 29 2025

     Today and tonight...

On the northern periphery of a mid/upper-level high centered
near El Paso, TX, early morning water vapor imagery and
objective analysis indicate prevailing northwest flow across the
northern and central Plains. Several vorticity maxima are
present within that regime, the most prominent of which is
currently moving into western SD. At the surface, a ridge axis
stretched from the upper Great Lakes into mid-MO Valley, with
calm or light and variable winds observed across eastern NE and
western IA as of 3 AM.

The light winds have allowed patchy fog develop --especially in
western IA-- where skies have remained cloud-free. Over eastern
NE, weak warm advection has fostered a gradual increase in
cloud cover, which should limit the potential for more
widespread fog development through daybreak. By later today
into tonight, increased forcing for ascent associated with the
western SD disturbance is expected to support an increase in
shower and thunderstorm activity across portions of western and
central NE. The CAMs differ on how far east that convection
will develop, with this forecast update indicating the best
precipitation chances (15-30% PoPs today, and 30-50% PoPs
tonight) across northeast NE.

The models indicate the strongest instability developing across
western and central NE this afternoon and evening, where the
best potential for isolated severe will exist. WPC is
highlighting portions of northeast NE in a slight risk for
excessive rainfall. But as mentioned above, there is
considerable model spread in how far east storms will develop,
so confidence in heavy rainfall is low.

Highs today will be similar to those on Thursday, with readings
in the mid 70s to low 80s.


     Saturday through Monday night...

The 00z global models are in good agreement in the slow
southeast progression of a midlevel low from the western
Dakotas through mid-MO Valley, in tandem with a weak surface
low. That pattern evolution will lead to continued cool
conditions, with an extended period of measurable precipitation
chances. It doesn`t look like a complete wash out, but potential
exists for for multiple waves of fairly widespread rainfall
(peak PoPs of 50-75%), especially from Saturday into Sunday
night. Current indications are that generally weak instability
will limit any severe weather potential. However, given the slow
motion of the synoptic system, and potential for recurring
precipitation episodes across the same areas, locally heavy
rainfall and attendant flooding appear possible, especially in
eastern NE.

Considerable cloudiness and areas of rain will support the
continuation of seasonably cool temperatures, with highs mainly
in the upper 60s to 70s.


     Tuesday through Thursday...

The upper-air system mentioned in the previous section is
forecast to shift southeast of the area on Tuesday, ahead of a
much stronger shortwave trough, which is expected to move
through the mid MO Valley on Tuesday night or Wednesday. The
latter midlevel disturbance will be linked with a surface cold
front, which will move through the area at the same time. This
forecast update will indicate lingering low (15-20%) PoPs on
Tuesday, with slightly better rain chances (PoPs increasing to
20-30%) on Tuesday night, with the movement of the front
through the area.

Highs in the 70s ahead of the front on Tuesday will cool into
the 60s and low 70s on Wednesday, with mainly 60s forecast on
Thursday.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 541 AM CDT Fri Aug 29 2025

Light winds and variable cloud cover have resulted in patchy fog
early this morning, which is likely to linger through about 14z.
Temperature-dewpoint spreads are zero at KOMA and KOFK as of
10z, suggesting a higher probability of fog development over
the next one to two hours. That spread is at three degrees at
KLNK, with a seemingly lower potential for fog formation there.
South or southeast winds will remain relatively light today, at
generally less than 10 kt. Tonight, shower and thunderstorm
chances increase in northeast NE, including KOFK. Confidence in
specific timing of any SHRA/TSRA occurrence is currently too low
to include in the forecast.

&&

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

&&

$$

DISCUSSION...Mead
AVIATION...Mead