975
FXUS63 KOAX 041021
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
521 AM CDT Fri Sep 4 2026

.KEY MESSAGES...

- Hot and humid weather continues with heat index values in the
  low 100s across southeast Nebraska and southwest Iowa. A Heat
  Advisory remains in effect through at least Saturday.

- Oppressive heat will continue into next week along with some
  small chances (10-30%) for nightly showers and storms. Warm
  lows in the 70s will provide little relief.

&&

.DISCUSSION...
Issued at 1132 PM CDT Thu Sep 3 2026

Tonight and Tomorrow:

Water vapor imagery this afternoon features the persistent cutoff
low over the Pacific Northwest while broad ridging holds over the
eastern two thirds of the CONUS. A few shortwaves continue to spur
on convection across northern Minnesota and the Mid-Atlantic, while
we continue to see southwesterly flow aloft south of the main
surface front draped across the Dakotas towards southern Michigan.
Dewpoints have been over-performing over the last two nights,
making the late afternoons/early evenings that much more humid,
with another warm night in store across the area. Lows across
southeast Nebraska into southwest Iowa will struggle to fall
below 75 degrees, while the coolest conditions only fall to
around 70 degrees. Low-level winds have already ramped up just
above the surface, though convergence along the nose of the low-
level jet will be pointed well to the northwest, limiting any
chances for rain.

Heading into Friday, another hot day is in store as the mid/upper
ridge holds over the area with no relief in sight. Afternoon
dewpoints in the mid 70s will continue hanging around northeast
Nebraska into northern Iowa, while slightly lower values remain
to the south where the hottest temperatures are anticipated to
be. A continued Heat Advisory will carry forward the message of
the dangerous heat -- not just due to the peaks of the heat, but
also the duration of the heat heading into the weekend. Heat
indices are forecast to top out in the 100-106 degree range,
with the worst conditions along and south of Interstate 80.

Saturday and Beyond:

Another warm early morning is expected to be interrupted by
convection initiating and being maintained by a nosing low-
level jet across eastern South Dakota while additional weaker
convection tries to pull itself together across central Nebraska
in worse convective ingredients. Once the strength of the LLJ
begins waning around sunrise, the weaker convection in central
NE should die while the MCS/cluster across South Dakota tries
eating into the better instability to its immediate south. As
it moves southward (and as time goes on), less and less shear
will be available to maintain its strength and the cluster
should fade as it pushes into northeast Nebraska and Iowa.
Lingering showers and pop-up storms will likely continue along
the outflow boundary throughout the afternoon northeast Nebraska
and western Iowa, with storm strength expected to be low.

Aside from the shower and storm chances, heat is expected to
continue as the main ridge across the area transitions from a center
over the eastern half of the CONUS to a position over the western
half. Temperatures take a slight dip for Saturday due to the
storm activity and resultant clouds, with temperatures expected
to rebound into next week. Overall rain chances through the
latter part of the forecast continue to remain rather low, owing
to the smaller-scale forcing for ascent that will occur, some
off the nocturnal jet while others drift in from afternoon
convection that initiates along a weak mesoscale boundary.
Ensemble models continue to lean towards the hot end of the
temperature forecast with us remaining planted on the eastern or
western edge of a building ridge heading into next weekend. A
"cold" front passage could bring in minor relief towards the
middle of the upcoming week, but we`ll still be left with above-
average temperatures that are still reminiscent of the deep
summer while most of the area continues looking forward to fall.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 520 AM CDT Fri Sep 4 2026

Low-level wind shear is wrapping up leaving mostly 5-10 knot sfc
winds forecast over the next 24 hours. Most winds will blow out
of the south with some variability in the direction at KOFK and
northeast Nebraska.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Heat Advisory until 7 PM CDT Saturday for NEZ044-045-050>053-
     065>068-078-088>093.
IA...Heat Advisory until 7 PM CDT Saturday for IAZ055-056-069-079-
     080-090-091.

&&

$$

DISCUSSION...Petersen
AVIATION...Nicolaisen