207
FXUS63 KOAX 171957
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
257 PM CDT Tue Jun 17 2025

.KEY MESSAGES...

- Scattered thunderstorms will develop and slowly drift across
  the area through this evening, with additional storms through
  Wednesday morning.

- The strongest storms this evening will produce lightning and
  localized heavy rain. There is a small chance (5%) for small
  hail or a 50+ mph wind gust. There is an even smaller chance
  (1%) for a brief tornado to develop.

- Temperatures will become quite hot for Friday through Sunday,
  with daily max heat index values of 100 to 110 degrees
  expected.

&&

.DISCUSSION...
Issued at 230 PM CDT Tue Jun 17 2025

The environment across the forecast area this afternoon is,
generally speaking, weakly capped, weakly sheared, and weakly
forced. There are pockets of weak forcing that have proven
sufficient to initiate convection since around 130 PM,
especially as the weak forcing interacts with areas that warmed
more effectively through filtered sunshine today. One region is
a diffuse frontal zone extending across northeast NE into
northwest IA where clusters of storms have developed. Capping is
weak to non-existent in this area, and with limited wind shear
the environment is similar to a summer pop-up storm day in the
south. Cells are developing, intensifying, and raining into
themselves, producing non-severe cold pools that push off and
initiate additional updrafts. Another zone of weak forcing is
associated with an MCV moving up I-80 out of south central NE.
The boundary layer ahead of this feature is a little drier and
thus slightly more challenging to initiate, but some cells have
gone up near Wahoo. The slightly drier boundary layer might
suggest a bit more potential for a strong wind gust with this
activity, but so far it has been unimpressive.

After this MCV passes through, should see a bit of net downward
motion in its wake which could tame precip chances for a bit
especially in the southern CWA. But as the night progresses
toward Wednesday morning, the last embedded short wave in the
progressive longer-wave system will move from north central NE
across eastern NE into Iowa by mid day Wednesday. This will be a
slow progression, and expect scattered to widespread convective
showers and some storms associated with that zone of ascent. It
will be interesting by Wednesday afternoon if some instability
can develop in advance of the system as it could bring some
potential for a few additional strong storms. The bigger thing
to watch may again be the potential for locally very heavy
rainfall with the slow moving system, ample atmospheric
moisture, and convective rain rates.

As we move into Friday, Saturday, Sunday, a long wave trough
will develop on the west coast with ridging building into the
Plains and east, and ample warm advection into the region.
Models are currently in strong agreement with keeping the area
precip free through Sunday as any forcing will be well northwest
of the forecast area. Temperatures are likely to surge into the
90s to around 100 each day, with some indications within the
ensemble envelope of conditions being warmer yet. Dewpoints will
also be on the increase and daily max heat index values are
likely to be in the 100 to 110 range. With this being the first
higher end bit of heat, will need to strongly consider heat
headlines in the next day or two, and may flirt with excessive
heat warning criteria in parts of the forecast area.

By Sunday night into next week, model agreement is strong in
the ridge breaking down slightly with the jet stream dropping a
bit closer to the local area. This is a favored scenario for
more frequent thunderstorm chances, and at least some potential
for a few rounds of severe storms and heavy rain, especially as
multiple rounds move overhead on consecutive days.


&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1238 PM CDT Tue Jun 17 2025

Lower than normal confidence in timing and intensity of
precipitation with scattered showers and perhaps some
thunderstorm expected at times. Tried to highlight most likely
times at each site, including the next couple of hours at OFK.
Then need to watch potential for MVFR or even IFR ceilings to
develop for several hours after 08Z and continuing through 16Z
or so. Some of this will depend on how expansive any
precipitation becomes, so again, confidence in the forecast
specifics is lower than normal.

&&

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

&&

$$

DISCUSSION...Barjenbruch
AVIATION...Barjenbruch