054
FXUS63 KOAX 132301
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
601 PM CDT Sun Jul 13 2025

.KEY MESSAGES...

- Warmer and humid through Tuesday.

- There is a 20% chance of storms in northeast Nebraska this
  afternoon and evening. If they develop, some could be strong
  to severe (5-10% chance), with damaging winds and hail the
  primary hazards.

- Potential exists for repeated rounds of storms beginning as
  early as late Tuesday afternoon, but questions remain on exact
  timing. If places do see multiple rounds of storms, flooding
  could become a concern again. Some severe weather is also
  possible.

- Cooler temperatures on Thursday into Friday

&&

.DISCUSSION...
Issued at 245 PM CDT Sun Jul 13 2025

     Late this afternoon through Monday...

Mid-level heights are building this afternoon from the northern
Plains into the mid-MO Valley in the wake of a short-wave trough
currently over the upper Great Lakes. In the low levels, a
surface front was analyzed from the eastern Dakotas into north-
central NE as of early afternoon, with that feature expected to
reach the far northwest part of our area late this afternoon or
early this evening before stalling. Latest visible satellite
data show a growing cumulus field along the boundary, which is
indicative of a gradually weakening cap.

Strong daytime heating coupled with some moisture advection and
evapotranspiration effects have contributed to moderately
unstable, pre-frontal air mass with MLCAPE of around 2000 J/kg.
Recent HRRR trends seem to be at odds with the satellite
observations in that the model has backed off on storm
development in our area through this evening. However, the
other CAMs indicate isolated storm development along the front
later today.

Despite the air mass becoming uncapped, the presence of the
mid-level height rises (implied subsidence) and weakening
convergence along the front may limit storm coverage to
isolated at best. On the condition that storms develop and
become sustained, deep-layer shear of 30-35 kt may support some
organization, with the potential for hail approaching severe
levels along with locally strong wind gusts.

Mid-level heights continue to build on Monday, with the
previously stalled surface front developing north into the
Dakotas in response to lee cyclogenesis over the northern High
Plains. High temperatures are expected to be a bit warmer than
those today, with readings in the upper 80s to low 90s.


     Tuesday through Thursday...

The 12z global models continue to advertise mid-level height
falls/troughing across the north-central U.S., due to the
progression of a lead disturbance through that area Tuesday and
Tuesday night, and a second, stronger system Wednesday
afternoon and Wednesday night. At the surface, the models have
come into a little better agreement in suggesting that a
convectively aided front will move into the area Tuesday night.
However, differences still exist on how quickly that boundary
clears our area to the south.

A warm and moist air mass will develop across the region on
Tuesday, with highs again in the upper 80s to low 90s. Dry
weather will continue through much of the day, with the models
in good agreement in the development of a large thunderstorm
complex over SD and north-central NE, which eventually moves
into our area Tuesday night. An associated risk for flooding
rainfall, damaging winds, and hail will exist with those storms
as they move through our area.

On Wednesday and Thursday, uncertainties in the exact frontal
position result in a low confidence in rainfall potential and
attendant flooding and severe-weather risks. This forecast
update will indicate the highest PoPs of 40-50% on Wednesday
night, coincident with the movement of the second mid-level
disturbance through the area, as mentioned above.

Temperatures will trend cooler with highs in the 80s to low 90s
on Wednesday, and 70s to low 80s on Thursday.


     Friday and Saturday...

The models indicate the movement of a low-amplitude disturbance
into the northern Plains on Friday, which will encourage the
northward advance of the previously mentioned surface front
back into or to the immediate north our area. There is some
signal for thunderstorm development along that boundary Friday
afternoon into Friday night within a seemingly favorable
environment for severe weather and flooding, so we will be
keeping an eye on that.

Slightly warmer highs in the 80s are forecast both days.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 554 PM CDT Sun Jul 13 2025

VFR conditions are expected to prevail through the period. An
isolated shower or storm may try to struggle into the KOFK
region between 00-04Z, however convection has been struggling
to hold together so far this afternoon. Otherwise, winds will
remain out of the south/southwest through the forecast period,
at 05-10 kts.

&&

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

&&

$$

DISCUSSION...Mead
AVIATION...KG