226
FXUS63 KOAX 300429
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1129 PM CDT Fri Aug 29 2025

.KEY MESSAGES...

- A cool and wet holiday weekend is in store for much of the
  area.

- Repeated rounds of heavy rain with embedded storms from early
  Saturday morning through Labor Day may lead to flooding in
  some areas. The threat of damaging winds and hail remains
  low.

- Cooler temperatures in the 60s and lower 70s continue mid to
  late next week with more comfortable humidity.

&&

.DISCUSSION...
Issued at 345 PM CDT Fri Aug 29 2025

Through This Evening:

A notable temperature gradient exists across the area this
afternoon with temperatures only in the upper 60s to lower 70s
along and west of Highway 81 where extensive cloud cover and
spotty light showers/drizzle have held down temperatures.
Meanwhile farther to the east, generally along and east of the
Missouri River, ample sunshine and deeper mixing have allowed
temperatures to warm into the low to mid 80s.

Meanwhile to the northwest, scattered thunderstorms have
developed over portions of north central NE/south central SD.
Model guidance shows the majority of this activity should remain
largely to the west of the local area through this evening as
storms propagate southward along the relatively north to south
oriented instability gradient. Nevertheless, spotty showers
can`t be ruled out generally north of I-80 in Nebraska this
afternoon and evening, with a stray storm possible in the
evening mainly west of an Albion, NE to Yankton, SD line (20%
chance).

Labor Day Weekend:

Focus continues to be on the long holiday weekend which is
looking increasingly cool and wet for much of the area. This is
due to a mid-upper low that is in the process of developing over
the north central Plains. Model guidance continues to trend
toward this feature (paired with a weak surface low) stalling
out over the local area through Labor Day which will allow for
repeated rounds of showers over eastern Nebraska and far western
Iowa.

While confidence is high in rainfall occurring through much of
the weekend, the confidence in onset time of the more
widespread shower coverage is lower due to continued model
variability in where convection redevelops late tonight into
early Saturday morning. With this in mind, the general
expectation is still for increasing coverage from west to east
through the morning and afternoon on Saturday (i.e. in the AM
near/west of Highway 77, and in the afternoon near and east of
the Missouri River).

Tall and skinny CAPE profiles, slow to near stationary storm
motions, and higher PWATs of 1.6-1.8" are all supportive of
heavy rainfall. Instability remains muted overall, but is
sufficient for embedded lightning strikes with any of the more
organized showers. While antecedent conditions have been fairly
dry the past several days, flooding concerns have increased due
to the potential for multiple rounds of heavy rain falling over
the same areas. In fact, nearly every member of the past three
cycles of EPS guidance have over 3-4" of rain falling through
the Saturday through Monday period. This combined with several
hi-res models having localized amounts in excess of 6" (with
varying placement and timing) supports ramping up messaging for
at least localized flooding impacts in the area. Accordingly,
WPC has included at least portions of the local area both
Saturday and Sunday in a Slight Risk of flash flooding (threat
level 2 of 4), and may eventually be needed for Monday. The
threat of damaging winds and hail remains low through this time,
though given the expected low LCLs, will have to keep an eye
out for any possible funnel clouds as can be the case with
closed upper lows.

The increased cloud coverage and showers beneath the closed
upper low will hold temperatures in the 60s to lower 70s for
much of the area through the holiday weekend.

Beyond Tuesday:

This system is posed to exit the region into Tuesday which will
then be followed by a more pronounced mid-upper level shortwave
that dives across the Midwest. An associated surface cold front
will push across the area late Tuesday into Wednesday morning
and bring additional shower and storm chances (20-30%). In its
wake surface high pressure sets up across the central and
northern Plains leading to cooler temperatures and lower
humidity through the end of the work week with highs in the 60s
WED-THU and lower 70s FRI.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1111 PM CDT Fri Aug 29 2025

Isolated to scattered showers and thunderstorms may develop
across northeast Nebraska around 09-12Z this morning, ahead of
an approaching storm system. Confidence in these earlier showers
impacting the KOFK area has lowered with the latest model runs.
The better chance for prevailing showers still looks to be
around 12Z at KOFK, 15Z at KLNK, and 18Z at KOMA. VFR conditions
early in the period will gradually deteriorate to MVFR and IFR
as showers move into the region. Precipitation is expected to
linger through Saturday night and into Sunday.

&&

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

&&

$$

DISCUSSION...Petr
AVIATION...KG