267
FXUS63 KOAX 072318
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
618 PM CDT Mon Sep 7 2026

.KEY MESSAGES...

- Warmer weather returns on today with highs in the upper 80s to
  low 90s. More storms are possible Monday night for northeast
  Nebraska (40-60% chance).

- High temperatures soar into the mid to upper 90s across
  southeast NE and southwest IA Tuesday before a cold front
  brings showers and storms (60-80% chance).

- Cooler weather arrives Wednesday and beyond, with highs in
  the upper 70s to mid 80s. More rain chances next weekend.

&&

.DISCUSSION...
Issued at 1245 PM CDT Mon Sep 7 2026

Clearing skies this morning will pave the way for another warm
day with highs mostly in the upper 80s to mid 90s this
afternoon. Ridging remains in place over the Central Plains with
a strong low-level jet advecting in warm-moist air. This is
leading to an axis of moisture oriented up the Missouri River
across eastern Nebraska and western Iowa. Subsidence from
ridging aloft and strong winds will help to mix down warmer
temperatures leading to a net drying effect in the sounding
profile. This should inhibit shower and storm development this
afternoon. We`re watching the front currently in Wyoming for it
to cross north into the Dakotas and drop south into NE Nebraska
tonight, triggering shower and storm chances for NE Nebraska
overnight into Tuesday morning. While we do have a Marginal Risk
(level 1 of 5) for severe storms, it looks like the better
chance for stronger storms should stay north in SE South Dakota.
Even that isn`t looking as good as it did in earlier runs of
the CAMs. Still, that`s where the better shear is found. Best
window for our area is probably midnight-2am, with some
potential as early as 9pm. Greatest hazards will be damaging
winds and large hail.

Tuesday we`ll have the frontal boundary, stalled across
northeast Nebraska through the morning. Looking at the upper-
level flow, the front appears to stall along the dampened ridge,
flattened by a series of troughs ejecting out of Washington and
British Columbia. The second trough finally kicks the crest of
the ridge east, allowing the front to drop south across the
rest of our area Tuesday afternoon and evening. With this,
expect a line of showers and storms to develop along the I-80
corridor and shift southeast across the rest of southeast
Nebraska and southwest Iowa Tuesday evening and overnight. While
we will be plenty unstable, shear is limited along and ahead of
the front making for only another Marginal Risk (level 1 of 5)
for severe storms.

We`re also monitoring the heat tomorrow along and south of the
stalled frontal boundary. With moisture pooling along the
frontal boundary and temperatures forecast to reach into the
mid-to-upper 90s, heat indices are forecast to hit 103-107
across much of southeast Nebraska and southwest Iowa. Lower
confidence right along the front from Lincoln through Omaha
eastward as shower and storm development may be occurring right
as we hit peak heating. This leads to a very short window of
opportunity for heat indices to hit Heat Advisory criteria of
105, while areas south have a better chance. Have issued a Heat
Advisory for areas with the best chance of hitting this
criteria.

Showers and storms will linger across far southeast Nebraska and
southwest Iowa into Wednesday morning, mostly clearing out by
the afternoon. Temperatures will be milder behind the front with
highs near normal for this time of year, in the upper 70s to low
80s. We stay dry and mild through Thursday as zonal flow
maintains across the region aloft and a cooler Canadian high
sits in place near the surface. Our next chance for showers and
storms looks to be Friday when a trough brings another front
through the region. The warm front lifting north in the morning
will bring temperatures back up into the mid-to-upper 80s
Friday afternoon with showers and storms expected to develop
along and ahead of the cold front Friday afternoon and evening.

Behind this next system, expect another Canadian High to
maintain seasonably mild temperatures with highs in the upper
70s to low 80s into the weekend. More rain expected Sunday into
Monday with broad troughing in place aloft helping to reinforce
northwesterly flow and CAA across our area.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 612 PM CDT Mon Sep 7 2026

VFR conditions are favored through the period. Southeasterly
winds gusting at 20-25 kts will continue before gradually easing
through the evening. Low-level wind shear is expected at each
terminal later this evening into the overnight period as a 45
kt southerly low-level jet moves in at FL017. A few showers are
possible (20% chance) across northeast Nebraska, near KOFK,
later this evening.

Into Tuesday, a cold front will push southward across the area,
shifting winds from southerly to northwesterly. Scattered
showers and thunderstorms are expected along and behind the
front. Confidence is high, particularly at KOMA and KLNK (80%
chance), for a period of showers and potential thunderstorms
Tuesday afternoon, though exact timing may need adjustments.
Patchy MVFR conditions are gusty winds will be possible under
any stronger storms.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Heat Advisory from 1 PM to 7 PM CDT Tuesday for NEZ066>068-078-
     088>093.
IA...Heat Advisory from 1 PM to 7 PM CDT Tuesday for IAZ079-080-090-
     091.

&&

$$

DISCUSSION...McCoy
AVIATION...Wood