429
FXUS63 KOAX 280450
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1150 PM CDT Fri Jun 27 2025

.KEY MESSAGES...

- Showers and storms, with a few strong to severe, will be
  possible this evening and Saturday evening across northeast
  NE. Damaging wind gusts (60-70 mph) and hail (up to 1") will
  be the primary hazards.

- Warm and humid conditions are expected Saturday afternoon,
  with Heat Index values peaking between 95 and 102 degrees.

- Additional storm chances return on Sunday. Dry weather is
  expected Monday and Tuesday, followed by off-and-on chances
  for showers and storms beginning Wednesday and continuing
  through the week.

&&

.DISCUSSION...
Issued at 232 PM CDT Fri Jun 27 2025

This Afternoon and Tonight...

This afternoon`s mid- to upper-level pattern reveals a complex
blocking setup, with generally zonal flow interrupted by a series of
shortwave disturbances moving through the northern Plains. As a
result, our region remains under a warm and moist air mass. Weak
surface high pressure will support mostly clear skies and
temperatures climbing into the upper 80s to low 90s.

Attention then turns to this evening, when the potential for severe
weather returns across portions of northeast NE. A weak mid-level
disturbance is forecast to move along the NE/SD border, interacting
with an unstable yet capped environment. A corridor of MLCAPE
exceeding 3000 J/kg is expected to stretch from central into
northeast NE, setting the stage for storm development. Convective
initiation is expected over the Sandhills during the afternoon, with
storms likely organizing into an MCS as they progress towards
northeast NE into the evening,

However, confidence in how far this system will hold together varies
among CAM guidance. Some CAM guidance (HRRR, NAM Nest, Fv3) weaken
the system before it reaches the area, while others (NSSL-WRF, ARW)
suggest a more robust MCS pushing deeper into northeast NE. Limiting
factors including weak forcing and only modest deep-layer shear (25-
30 kts), which may prevent any organized storms from pushing into
the area. Still, if storms do hold together, they will be capable of
producing damaging wind gusts (60-70 mph) and hail (up to 1"). The
SPC currently highlights northeast NE in a slight risk (level 2 of
5) for severe weather. Due to the uncertainty in storm
evolution, PoPs remain conservative in the 20-40% range.

Saturday...

The upper-level pattern will transition into a broad trough over the
northern Plains by Saturday, with a series of embedded disturbances
continuing to pass through the region. In the morning, some patchy
fog may develop across southeast NE and southwest IA, though breezy
winds should help limit it to low-lying or wind protected areas. A
warm and moist air mass will persist into Saturday, with high
temperatures climbing into the low to mid 90s and dewpoints peaking
in the low to mid 70s. These conditions will push afternoon Heat
Index values into the 95 to 102 degree range, just shy of Heat
Advisory criteria, but still something to be mindful of if you have
outdoor plans.

Another weak disturbance moving across the northern Plains is
expected to spin up a surface low over western SD, which will track
toward southeast SD through the day. A cold front associated with
this system will extend south-southwest and progress into northeast
NE Saturday evening. Ahead of this front, there will be a chance for
convective development Saturday evening. While instability will once
again be ample, shear will remain modest, in the 25-30 kt range.
CAMs once again show differing solutions regarding storm coverage,
likely due to the weaker synoptic forcing. The greatest chance for
strong to severe storms will once again be across northeast NE,
close to the surface low, where the SPC maintains a slight risk
(level 2 of 5) for severe weather. The primary hazards with any
storms that develop will be damaging wind gusts (60-70 mph) and
hail (up to 1"). Due to lingering uncertainty in storm
coverage, PoPs remain in the 20-45% range.

Sunday...

The aforementioned cold front is expected to move through the area
on Sunday, with high temperatures dependent on the timing of its
passage. Ahead of the front, highs could reach the low to mid 90s
across southeast NE and southwest IA, with areas behind the front
likely remaining in the mid 80s.

Scattered to widespread thunderstorm development is expected through
the afternoon and evening as the front progresses southeastward,
with PoPs of 50-75%. The potential for a few strong to severe storms
will hings on how much instability and clearing we can get from
overnight convective debris. The SPC currently places the entire
forecast area in a marginal risk (level 1 of 5) for severe weather.
In addition to the severe threat, localized heavy rainfall will be
possible, on top of already saturated soils. The WPC has outlined a
marginal risk (level 1 of 4) for excessive rainfall, supported
by precipitable water values between 1.5-2.0" (above the 90th
percentile for late June) and a warm cloud depth of 3-4 km,
conditions that favor efficient rainfall production.

Monday and Beyond...

Precipitation may linger into Monday morning before clearing out,
with afternoon highs expected to reach the upper 80s. Warm
conditions will continue into the first half of the work week, with
highs generally in the upper 80s to low 90s.

The mid- to upper-level pattern next week is expected to feature a
weak trough over the northern Plains and Great Lakes region, with
weak riding in place over the southwestern CONUS. This setup will
allow shortwave disturbances to pivot through the main trough axis,
potentially bringing showers and thunderstorms to the area,
particularly from Wednesday through Friday. PoPs during this period
range from 20-40%. GEFS based machine-learning guidance highlights
mid- to late week as a period to watch for potential severe weather,
though confidence remains low in exact timing and location in this
extended time frame.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1150 PM CDT Fri Jun 27 2025

VFR conditions hold through the TAF period with winds out of the
south. Winds will increase, gusting to 20-25kt Saturday
afternoon, then calm back down to around 8-10 kt for Saturday
evening. KOFK should watch toward the end of the TAF period as
models don`t have a great handle on timing of storms moving into
northeast Nebraska, anytime between 00-06Z Saturday night. For
now, have left out of this TAF package.

&&

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

&&

$$

DISCUSSION...Wood
AVIATION...McCoy