751
FXUS63 KOAX 190713
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
213 AM CDT Tue Aug 19 2025

.KEY MESSAGES...

- Fog is expected across much of the area this morning, with
  patchy areas of visibility below 1 mile.

- Near to slightly above average temperatures will continue
  through Thursday with highs generally in the upper 80s.

- Temperatures will drop below average this weekend, with highs
  in the 70s to low 80s through the weekend. Periodic rain
  chances begin Thursday night and continue through the weekend.

&&

.DISCUSSION...
Issued at 211 AM CDT Tue Aug 19 2025

Today and Tonight...

A mid- to upper-level ridge centered over the Four Corners region
continues to maintain northwesterly flow aloft across the area. At
the surface, a diffuse boundary remains draped from northeast KS
into northwest MO with surface high pressure pulling into northeast
NE. A weak disturbance and associated vorticity maxima are moving
into west-central KS, where a loosely organized thunderstorm complex
persist as of 1 AM. This complex is expected to shift east
overnight, though CAM guidance has trended toward keeping it south
of the NE-KS border. While a storm or two could graze far southeast
NE this morning, probabilities have notable decreased (PoPs peak at
15%). MLCAPE remains potent across this area (1500-2000 J/kg), but
weak shear and forcing for ascent will cap storm organization.
Should a storm manage to cross into the area, damaging wind gusts
(up to 60 mph) and locally heavy rainfall would be the primary
hazards. SPC does maintain a Marginal Risk (Level 1 of 5) for severe
weather across far southeast NE for the morning hours.

Another item of note this morning will be fog development,
especially north of Interstate 80 where surface high pressure is
bringing calm winds. Visibility may drop below 1 mile in this area,
particularly in low-lying and wind protected areas. Conditions
should gradually improve after sunrise, yielding a mild and mostly
clear afternoon. Highs will run slightly above average, topping out
in the upper 80s to low 90s. Heat indies will generally peak in the
mid to upper 90s.

Wednesday and Beyond...

Fog is likely to develop again Wednesday morning as the day starts
with calm winds and residual low-level moisture. CAM guidance is
hinting at a weak surface trough/MCV pushing across the area later
Wednesday morning/afternoon. Low end PoPs (15%) have been introduced
for this potential. Afternoon highs Wednesday and Thursday will run
near seasonal norms in the mid to upper 80s, with overnight lows
dipping into the mid 60s. During this time, the mid- to upper-level
ridge will gradually build overhead, shielding the area from
disturbances and limiting notable precipitation chances.

By Thursday night into Friday, a stronger shortwave disturbance will
round the ridge, dampening it and helping to drive a cold front
south through the area. Precipitation chances return late Thursday
and early Friday (PoPs 15-30%) with this passage. While long-range
guidance keeps the better forcing to our north, there may be just
enough shear and instability across northeast NE to support a few
stronger storms. We will have to see how the details shake out as it
approaches.

Highs on Friday will depend on frontal timing with the low 90s
possible ahead of the boundary, while areas behind it may only reach
the low 80s. Showers are expected redevelop along the front Friday
afternoon/evening as it pushes to the south. A high-amplitude trough
building over Ontario/Quebec this weekend will enhance northwesterly
flow and CAA into our area. Highs on Saturday are currently expected
to top out in the upper 70s to low 80s, with widespread 70s likely
on Sunday and Monday. Overnight lows will fall into the 50s. The
dampened ridge will also allow several weak disturbances to pass
through over the weekend, bringing occasional precipitation chances
(PoPs 15-30%). However, dry periods should outnumber wet ones.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1139 PM CDT Mon Aug 18 2025

Confidence has increased in fog development, particularly along
and northeast of a line from KBVN to KOLU to KFET to KOMA. Have
introduce BR for KOFK and KOMA after 11z, with visibilities
expected to drop to MVFR. Brief reductions to IFR may occur at
KOMA between 12 and 14z. Visibilities should improve after 15z
with VFR conditions persisting for the remainder of the TAF
cycle. Uncertainty remains on whether KLNK may see fog so have
left mentions out for this issuance, however, expect further
refinements and future amendments.

A scattered shower or storm may occur at KLNK after 10z, but
confidence remains well below 50% for inclusion in the TAF at
this time.

Winds will remain light throughout the period, becoming
northeasterly at all terminals after 15z.

&&

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

&&

$$

DISCUSSION...Wood
AVIATION...Castillo