058
FXUS63 KGID 170621
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
121 AM CDT Thu Sep 17 2026

.KEY MESSAGES...

- Widespread fog has already developed across the forecast area
  early this morning. Some locations are already at/near
  1/2-1/4, a trend that is expected to spread over the coming
  hours. A Dense Fog Advisory is in effect through 10AM.

- How quickly fog and any low clouds diminish today will drive
  how high temperatures do...if things linger longer into the
  day than currently expected, could mess with
  highs...especially for NNErn areas. Current forecast has
  highs in the mid 70s north to low 90s south.

- Chances for storms returns this evening/tonight, with better
  chances being focused mainly off to our NNW. An unsettled
  weather pattern keeps storm chances around through the
  weekend.

- High temperatures peak on Friday with widespread 80s-90s
  currently forecast...falling back into the 60s-70s by Sunday.

&&

.UPDATE...
Issued at 116 AM CDT Thu Sep 17 2026

Currently...

West-southwesterly flow remains in place across the area
tonight...with upper air and satellite data showing high
pressure anchored over the Gulf Coast region, broad/weak
troughing over central/eastern Canada, with the main area of low
pressure spinning over northern CA. Subtle forcing sparking of
some isolated/scattered showers/storms around the area...with
models showing potential for activity over portions of our
forecast area as we further into the early morning hours.
Looking at the surface, the pattern across the area remains a
weak one...with a stalled out frontal boundary draped east
through central KS. Winds across our forecast area remain
light/variable. Along with precipitation chances the rest of
tonight...potential for dense fog is also a concern, with a few
locations having already dipped down to/near 1/4 of a mile. A
Dense Fog Advisory is in effect through 10AM for the entire
forecast area.

Today and tonight...

Models are in good agreement showing little overall change in
the upper level pattern through this short term
period...remaining southwesterly as that West Coast low/trough
starts inching its way east. Main question marks for the daytime
hours will be driven by things happening before the sun comes
up...precipitation chances and the fog.

As far as precipitation chances go...expecting that isolated-
scattered activity to develop over the coming hours...gradually
lifting NE and diminishing with time...but there are
uncertainties with the timing of it exiting the area. Many of
the hi-res models have little going on through the afternoon
hours. Models showing a stronger shortwave disturbance working
onto the Plains this evening/tonight...but continue to largely
keep the best chances for storms off to the NNW of the forecast
area. Have some 20-40 percent chances clipping western and
northern portions of the area this evening/tonight...dry further
south.

As for the fog and any lingering stratus...main concern here as
well lies with the timing of improving conditions this
morning. Dense Fog Advisory currently runs through 10AM...but
some guidance suggests a small area could be slow to diminish
and hang around closer to midday. Forecast highs are trended
toward things improving by midday-early afternoon, allowing for
the chance to warm up, especially across northern
areas...sitting in the mid 70s north to low 90s south which
should clear out much earlier. The longer any of that
fog/stratus sticks around, the less time temps will have to
recover...not out of the question that mid 70s would be tough to
reach if it lingers longer.

Friday on...

The continued unsettled pattern keeps storm chances in the
forecast through the upcoming weekend. Models remain in pretty
good agreement looking at the big picture and the evolution of
that upper level currently over the West Coast. By Friday
evening, models showing the central of the low roughly in the
OR/ID/NV border area...with the potential for a shortwave
disturbance ejected out ahead of the main troughing to swing
through the Plains through Friday night. An accompanying surface
frontal boundary will be working its way south into the
area...but uncertainties linger with just how far it progresses.
The daytime hours on Friday are currently dry, with at least
scattered storms possible during the evening/overnight hours
along that boundary. Not out of the question some could be
strong- severe, with warmer temps climbing well into the 80s-90s
and better instability developing...but current SPC Day 2
Marginal Risk areas are mainly focused just out side the
forecast area.

This weekend...that upper low/trough continues inching
east...and if anything, compared to 24hrs ago, models have
slowed a touch. 24hrs ago models were showing its main passage
coming mainly late Sat night-Sun...recent runs are more in the
Sun night-Mon AM time frame...so obviously plenty of details yet
to figure out. Highest precip chances are currently focused in
the 00Z Sunday-12Z Monday time frame. First part of next work
week looking drier...but confidence isn`t overly high at this
point with so many other things to iron out before then.

As far as temperatures in the mid-long term...Friday is the
overall warmest day in the 80s-90s. Expecting more 70s-80s for
Saturday, then dropping into the 60s-70s for Sunday through
Tuesday.

&&

.DISCUSSION...
Issued at 245 PM CDT Wed Sep 16 2026


Brief Synopsis...

Higher pressure across the southeast U.S. with a cutoff low centered
across northern California and southwest Oregon today, keeps the
Central Plains region underneath southwest flow. This pattern tends
to be fairly unstable as it only takes a weak embedded shortwave
disturbance to initiate scattered showers or thunderstorms (lower
than usual short-term forecast confidence). The better forcing for
widespread precipitation will come over the weekend when the cutoff
low weakens back to a broad trough and takes a run at the central
U.S. Overall, high temperatures will be on track to peak for the
week on Friday (mid 80s to low 90s) before embracing the 70s for
much of the start of next week.


Tonight...

Low-level stratus continues to loom across the area this afternoon,
helping to keep highs from escaping the 70s. Though a few pockets of
drizzle or light rain can`t be ruled out tonight (20-50% chance),
the latest models have seemed to back off some with the
precipitation potential (10-30% HREF probs). In all, the best time
window for any coverage of scattered light rain showers will mainly
occur between the 1-9AM time range. Accumulations will be minimal
(<0.25") with most areas only receiving a trace to a few thousandths
of an inch of precip. The other main weather concern tonight would
be for the possibility of dense fog. Virtually all HREF members
(80%) including the RRFS, point towards a widespread coverage of
dense fog tonight. Given the weak easterly surface winds (upslope
flow) with high moisture concentrations (60s dewpoints), the
potential for fog development appears almost certain. In addition,
forecast lows are projected to reach the 60s (approaching dewpoints),
a high indicator for condensation or fog.


Thursday & Beyond...

Temperatures will gradually rise a through Friday (mid 80s to low
90s highs) as clearing skies couple with southerly warm air
advecting winds once more. This heat will likely remain short-lived
as a cold frontal passage overnight Friday flips the winds north
again, dragging in a cooler and drier airmass. Highs on the
other side look to return to the 70s to mid 80s Saturday and the
upper 60s and 70s Sunday through Tuesday.

The next best chance for precipitation (20-50%) lies overnight
Friday with the coming of the cold front (and the upper-level
trough/disturbance aloft). The main uncertainty at the moment would be
for how far south and west thunderstorms are able to form. The
latest high-resolution models/CAMs paint much of northeast Nebraska
to be under siege from these storms with a few initializing across
central nebraska. Conditions wise, the instability axis (the most
common path for storms to follow ... where CAPE >2,000J/kg) is
modeled to set up just northeast of the Tri-Cities. The factors
that, however, keep confidence for severe convection low for now
would be from minimal shear (20-30kts) and degrading lapse rates
overnight that could thwart overall storm intensity. In case of an
earlier arrival of storms Friday evening instead of night (slightly
more severe conducing ingredients), the SPC includes the southeast
2/3rd of the area under a marginal risk (level 1 of 5) for severe
weather. Scattered storms chance return Saturday and Sunday.

Looking well beyond for the end of week forecast next week, highs may
be possible to warm back up a few degrees. Cluster analysis begins to
diverge between the next Wednesday to next Saturday timeframe as
the ensembles start to show more variance (spread of possibilities).
The leading cluster, explaining around 40% of the variance, favors
broad ridging in the central U.S. This pattern would support the
warmer temperatures and possibly a less frequency of precipitation
chances.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1122 PM CDT Wed Sep 16 2026

For KGRI/KEAR Airports:

LIFR stratus and fog will persist across central Nebraska
through the morning hours as winds remain almost completely
calm.

Visibility will start to improve after sunrise, but some
restricted visibility could persist through midday along the
Platte River valley. Stratus is expected to finally scatter out
in the mid afternoon (20-22Z).

East to southeast winds are expected Thursday. LLWS is possible
Thursday night, but this is likely to begin very near or just
after the end of this TAF window. Given the ongoing fog
concerns, this was not included in this TAF issuance.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...Dense Fog Advisory until 10 AM CDT this morning for NEZ039>041-
     046>049-060>064-072>077-082>087.
KS...Dense Fog Advisory until 10 AM CDT this morning for KSZ005>007-
     017>019.

&&

$$

UPDATE...ADP
DISCUSSION...Stump
AVIATION...Mangels