047
FXUS63 KOAX 040749
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
249 AM CDT Thu Sep 4 2025

.KEY MESSAGES...

- Wildfire smoke lingers through this afternoon, before
  diminishing tonight.

- Isolated to widely scattered storms are possible late this
  afternoon into tonight. A strong storm or two is possible,
  with a risk for hail and gusty winds.

- Unseasonably cool weather will continue into early next week,
  with overnight lows potentially dipping in the upper 30s at
  some locations this weekend.

- Warmer temperatures by the middle to latter part of next week.


&&

.DISCUSSION...
Issued at 249 AM CDT Thu Sep 4 2025

Today and Tonight:

A vigorous shortwave trough located over Alberta and Saskatchewan
early this morning will continue southeast into the northern Plains
and upper MS Valley today, before eventually reaching the upper
Great Lakes tonight. The strongest height falls/forcing for
ascent will remain just to the north of our area; on the
immediate cyclonic side of a mid-level jet streak nosing into
the mid MO Valley. Meanwhile at the surface, a ridge of high
pressure currently centered over our area will build southeast,
ahead of a cold front that is expected to move into northeast NE
this afternoon, and eventually through the entire forecast area
by midnight.

The influx of a cooler, Canadian air mass has allowed
temperatures and dewpoints to drop into the 40s early this
morning, with patchy fog being observed across the area.
However, as winds switch to southwest today, dewpoints will
increase back into the 50s and perhaps low 60s ahead of the cold
front approaching from the north. Moisture increase will
combine with warmer afternoon temperatures in the 70s to create
a narrow axis axis of modest instability (MLCAPE of 500-1000
J/kg) immediately ahead of the front.

Latest CAM data indicate widely scattered thunderstorms developing
along the front in southeast SD, southwest MN, and northwest IA this
afternoon into early evening, within the zone of stronger mid-level
height falls preceding the shortwave trough. The models differ in
how far west/southwest the storms build along the front into
our area owing to the weaker forcing for ascent with southward
extent. Given that uncertainty, this forecast update will
maintain relatively low (20-30%) PoPs from this evening through
tonight. Deep-layer shear is forecast to be strong owing to the
presence of the mid-level jet streak, with a conditional risk
for a strong to severe storm or two, given sufficient
instability and convergence/uplift to form and sustain deep
updrafts. Hail and strong wind gusts will be the primary hazards
with any more intense storms that develop.

The models indicate the wildfire smoke lingering in the forecast
area through this afternoon, with concentrations decreasing
overnight behind the front moving through the area.


Friday through Sunday:

Outside of the potential for a few lingering showers in
southeast NE Friday morning, dry conditions are expected this
period as surface high pressure builds into the region.
Temperatures will trend cooler in the wake of the Thursday night
frontal passage, with highs mainly in the 60s, and lows in the
upper 30s to 40s.


Monday through Wednesday:

The 00z global models indicate that an amplified, mid-level
ridge initial over the Rockies will weaken while shifting east
into the Great Plains, ahead of a trough moving onto the Pacific
coast. In the low levels, a lee trough will deepen over the High
Plains, with strengthening south winds east of that feature
drawing a warmer and more moist air mass into the mid MO Valley.
There is some model signal that a weak disturbance will progress
through the eastard-building ridge, supporting rain chances on
Monday night. Otherwise, the main story this period is the
warming temperatures, with afternoon highs in the 70s. Some 80s
appear possible by Wednesday.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1140 PM CDT Wed Sep 3 2025

VFR conditions will prevail at the terminals through the
forecast period. Light and variable winds overnight will
increase to 10-15kts from the southwest tomorrow afternoon.
Our next chance (20-30%) of showers/t-storms is expected
Thursday evening through the end of the TAF period.

&&

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

&&

$$

DISCUSSION...Mead
AVIATION...ANW