594
FXUS63 KOAX 132354
AFDOAX

Area Forecast Discussion
National Weather Service Omaha/Valley NE
654 PM CDT Sat Sep 13 2025

.KEY MESSAGES...

- A chance of showers and thunderstorms Sunday into Sunday night
  (30-50%). A few strong to severe storms are possible. Rain
  chances return Tuesday afternoon into at least Thursday.

- Cooler, but still above-normal highs in the 80s Sunday through
  Tuesday. Temperatures fall into the 70s Wednesday through
  Friday.

&&

.DISCUSSION...
Issued at 316 PM CDT Sat Sep 13 2025

Rest of this afternoon and tonight:

Early afternoon water vapor imagery and objective analysis show
a mid-level trough centered over the Rockies, with an embedded
vorticity maximum located near the Four Corner region, within
the trough base. The vorticity maximum will progress northeast
into the High Plains tonight, in tandem with mid/upper-level jet
streaks, and a concentrated area of height falls/forcing for
ascent. At the surface, a weak area of low pressure was analyzed
over eastern SD, with an associated cool front extending
southwest from the low through north-central into southwest NE,
before linking with a secondary low over northeast CO. Ahead of
the front, deep, boundary-layer mixing has allowed for the
downward transfer gusty southwest winds and warm air aloft, with
3 PM temperatures in the upper 80s to mid 90s across our area.
Even though record high temperatures will remain out of reach,
it`s still a hot day by September standards.

Latest CAM data indicate a gradual increase in shower and
thunderstorm development across the central High Plains this
afternoon into tonight, within a zone of forcing for ascent
preceding the mid-level trough. A few showers and thunderstorms
could spread east into central NE overnight along the low-
level jet; however, our area is expected to remain dry.


Sunday and Sunday night:

The above-mentioned, mid-level trough is forecast to consolidate
into a closed low over western parts of SD and NE, with an
embedded vorticity maximum pivoting through the eastern side of
the trough across the mid MO Valley Sunday night. The progressive
nature of the embedded perturbation will encourage the eastward
advance of widely scattered showers and thunderstorms into our
area, mainly Sunday afternoon into Sunday night (peak PoPS of
30-50%). Rainfall is likely to be streaky, with many locations
probably not seeing a whole lot, and a few areas seeing an inch
or more.

There is a consistent model signal for the development
of a more organized thunderstorm line over central NE Sunday
afternoon, which moves into our western counties Sunday evening,
before weakening. The forecast environment ahead of that line
features modest amounts in instability and vertical shear, which
will limit the potential for a more robust severe-weather
threat. Nonetheless, the presence of moderately steep lapse
rates and a unidirectional wind profile will support the risk
for isolated occurrences of strong wind gusts and/or hail
approaching severe levels.

High temperatures on Sunday will be a function of cloud cover
and the areal extent of any shower and thunderstorm activity.
This update will indicate readings ranging from the low 80s in
our northeast NE to around 90 in extreme southwest IA.


Monday through Friday:

The mid-level trough discussed in the previous section will
continue northeast through the northern Plains and upper MS
Valley, ahead of another trough evolving across the northern
Intermountain Region. The 12z global models indicate the latter
disturbance slowly progressing east, and eventually stalling
across the northern and central Plains into upper MS Valley.
Monday and Tuesday are expected to remain warm ahead of the next
trough, with highs in the 80s. Precipitation chances increase
Tuesday afternoon into Tuesday night, and continue at least
Thursday as the mid-level system stalls across the region.
Maximum PoPs of 40-70% are forecast Tuesday night.

The various ensemble-based, machine-learning systems indicate
some severe weather potential on Tuesday afternoon and evening
with the movement of a surface cool front into the area. Pockets
of locally heavy rain also appear possible. Daytime temperatures
cool into the 70s behind the front from Wednesday through
Friday.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 634 PM CDT Sat Sep 13 2025

VFR conditions prevail at the terminals through the forecast
period. Southerly winds around 5-10kts continue through 18Z,
increasing in the afternoon. There will be a period potential
low-level wind shear at KOFK from 06-08Z and at KLNK from
12-15Z. After 15Z, there will be a 20-40% chance of showers and
storms at the terminals. Held off on putting this in prevailing
conditions for now due to low confidence on the timing of direct
impacts to the terminals.

&&

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

&&

$$

DISCUSSION...Mead
AVIATION...ANW

NWS OAX Office Area Forecast Discussion