254
FXUS63 KOAX 062237
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
537 PM CDT Sun Sep 6 2026

.KEY MESSAGES...

- Scattered showers and thunderstorms are expected this
  afternoon and evening. A few storms may become strong to
  severe, with isolated damaging winds and hail.

- Very heavy rainfall will also be possible with any storms that
  develop. A Flood Watch has been issued for flash flooding
  potential in parts of western Iowa through tonight.

- Above-average temperatures continue through Tuesday, with heat
  indices up to 100-105.

- A cold front will move through Tuesday into Wednesday,
  bringing high temperatures in the 80s along with periodic
  chances for showers and thunderstorms.

&&

.DISCUSSION...
Issued at 1216 PM CDT Sun Sep 6 2026

Today and Tonight...

Water vapor imagery and largescale analysis revealed a cutoff low
churning over the Pacific Northwest, and a prominent ridge
established over the center of the nation. A shortwave rippling
around the upper ridge brought bubbling convection across the area
today. Storms went up quickly, fueled by around 2000 J/kg of
instability, but struggled to maintain organization long enough to
produce severe wind or hail in a weakly sheared environment. By
noon, the persistent cloud cover and scattered precip maintained
temperatures in the 70s and 80s, which was pleasantly cooler than
the extreme heat of the previous several days.

CAMs still indicate the potential for more organized cells to become
established late this afternoon and evening, as marginally better
shear overspreads the region. If deeper convection does develop,
large hail, and damaging winds will be possible. However, the
lingering morning showers and storms could inhibit this later
development, keeping the best chance for a strong to severe storm
mainly east of the Missouri River, in western Iowa. Additionally,
high PWats, up to 2 inches, in conjunction with slow moving storms
initially could lead to areas of very heavy rainfall. CAM QPF
depicts several pockets of 1-3" with potential for up to 5"+
amounts. Therefore, a Flash Flood Watch has been issued for parts of
far western Iowa, where heaviest rainfall is expected.

Monday and Tuesday...

Spotty showers and storms will linger into Labor Day, as the
shortwave continues to traverse the upper ridge. The previously
mentioned Pac. NW low will finally eject eastward on Monday,
dragging a cold front toward the central CONUS. Temperatures on
Monday will be similar to today, with cloud cover providing some
relief and the shortwave shunting the thermal ridge. Winds will
increase ahead of the approaching system Monday afternoon, with
gusts up to 35 mph possible.

The cold front finally arrives Tuesday. While exact timing and
specifics remain a little uncertain at the moment, expect strong
southwesterly flow ahead of the front to pull temperatures back into
the upper 90s across southeast Nebraska and southwest Iowa, with
heat indices rising to 100-105. Showers and storms look likely
with the frontal passage, with at least a Marginal Risk (5%
chance) for severe storms in the afternoon and evening.

Wednesday and Beyond...

Showers and storms associated with the frontal passage clear the
area Wednesday, with zonal flow aloft will returning by mid-week,
dropping high temperatures back into the 80s. Periodic rain chances
of 15-30% remain in place through the remainder of the week as a
shortwave disturbance traverses the area. Good news for the fall-
lovers, looking further ahead, most GEFS and EPS-AIFS members
continue to bring a potent trough across the northern Plains next
weekend. This system will bring a push of cooler air into the region
and could knock highs into the 70s by the end of next weekend,
though details on timing and extent will still need to be ironed out.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 532 PM CDT Sun Sep 6 2026

Scattered thunderstorms continue across southwest Iowa this
evening, with patchy MVFR to LIFR conditions under isolated
heavier storms. Otherwise, VFR conditions are favored through
the period. The bulk of thunderstorm activity should remain east
of the TAF sites, though a brief period of thundershowers will
be possible (30% chance) at KOMA through 07/04Z. The
thunderstorms are pushing an outflow boundary to their west,
bringing brief periods of gusty north-nothwesterly winds before
returning to southeasterly.

Thunderstorms will taper off through the late evening, with a
few scattered showers possible into Monday morning. Otherwise,
south- southeasterly winds will increase through Monday morning
and afternoon, with gusts up to 20-25kts.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...Flood Watch until 4 AM CDT Monday for IAZ043-055-056.

&&

$$

DISCUSSION...KG
AVIATION...Wood