998
FXUS63 KGID 031132
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
632 AM CDT Wed Sep 3 2025

...Aviation Update...

.KEY MESSAGES...

- Spotty showers/a few mainly weak thunderstorms possible at
  some point today through around 7 PM near/behind a passing
  cold front, but looking increasingly-likely that any truly
  severe storm potential should focus at least slightly south-
  through-southeast of our forecast area (CWA).

- Another chance for isolated/scattered thunderstorms arrives
  Thursday evening-overnight with yet another cold front.
  Although still plenty of uncertainties regarding storm
  likelihood/coverage, this setup might actually feature a bit
  greater chance for a few strong/severe storms.

- Wildfire smoke concerns: Although there are no official Air
  Quality Alerts at this time (those decisions are made by
  Nebraska state government agencies), it is looking
  increasingly likely that at least modest concentrations of
  wildfire smoke will invade our CWA from the north this
  afternoon-tonight, and possibly linger into Thursday.

- Precipitation-wise beyond Friday AM: Confidence fairly high in
  prevailing dry weather at least Friday afternoon-Sunday, with
  low/uncertain chances for showers/storms returning Mon-Tues.

- Temperature-wise "big picture": Although parts of our CWA will
  get into the 80s today and Thursday, MOST places will see a
  prevailing slightly-cooler-than-average regime persist through
  the next week, with high temps mainly 70s and lows mainly 50s
  (and even 40s mainly Fri night).

&&

.DISCUSSION...
Issued at 510 AM CDT Wed Sep 3 2025

-- 7-DAY FORECAST BIG PICTURE COMMENTS, CHANGES, UNCERTAINTIES:

- Overall, no big changes of note through our 7-day compared to
  24 hours ago. In the longer term, if anything rain chances
  look even more spotty/uncertain for early next week, and in
  tandem forecast high temps have nudged up a few degrees. In
  the shorter term (next 48 hours), we have two distinct chances
  for at least limited/spotty thunderstorm activity and also a
  little bit of a "messaging dilemma" regarding them (see next
  paragraph), and also increasing concern for at least modest
  surface wildfire smoke concentrations (this has been
  officially introduced to our Hazardous Weather Outlook
  (HWOGID).

- Tricky thunderstorm chances/messaging next 48 hours:
We have at least low-end chances for isolated to perhaps
scattered thunderstorm activity associated with two separate
cold fronts over the next 48 hours (one today and the next
Thursday evening-overnight). Based on the latest model
data/trends, it appears increasingly-likely that any potential
for truly severe storms late this afternoon-early evening should
focus south-southeast of our CWA altogether within
central/eastern KS (although SPC`s initial Day 1 outlook did
maintain a level 1/Marginal Risk for parts of our KS counties.
On the flip side, some (not all) model data suggests that
Thursday night MIGHT feature an overall-better potential for a
few strong/severe storms (especially if the cold front would
happen to slow a bit), but at this time SPC has opted for only
"general thunder" on its initial Day 2 outlook (would not be
surprised to see a Marginal Risk introduced in later outlooks if
things trend toward the more aggressive solutions).


--- 7 DAY FORECAST CHRONOLOGICAL DETAILS (heavily focused on
 first 48 hours):

-- CURRENT/RECENT WEATHER SCENE AS OF 4 AM:
Briefly looking back over the last 12 hours, a few isolated
thunderstorms tried flirting with our far western CWA late
yesterday afternoon-evening (but failed to invade), while
another very localized batch of weak showers/storms briefly
tracked southward from Nance-through-York counties in our far
northeast early in the overnight. Since those faded away it`s
been a very uneventful/tranquil overnight, featuring mostly
clear skies, light generally westerly breezes, and no real fog
concerns (low temps on track to bottom out upper 50s most
areas).

In the big picture aloft, water vapor satellite and short term
model data confirm continuednorth-northwesterly flow over our
region, directed between a high-amplitude high/ridge over hte
western U.S. and broad/large-scale troughing over the eastern
half of the country. Of note is an upper low/shortwave trough
gradually diving south-southeast from Manitoba/Ontario toward
the Great Lakes (this system will drive through today`s initial
cold front).



-- TODAY-EARLY THIS EVENING: (through around 7pm):
- Precipitation/thunderstorm potential:
Although the majority of our CWA carries anywhere from a 10-20%
chance of seeing a rogue shower/sprinkle or mainly weak
thunderstorm at some point before 7 PM, the latest high-res
models (HRRR/NAMNest) strongly suggest that a good majority of
our CWA will likely remain dry (especially with regard to more
than sprinkles), with only increasing clouds (initially higher-
level but eventually some lower clouds) arriving from north-to-
south. As touched on above, SPC has technically included some of
our KS counties in a Marginal Risk for severe storms, but unless
the cold front slows down from current expectations, it "should"
be at least slightly south-southeast of our CWA altogether
before any late afternoon/early evening severe storms would form
along it. Certainly cannot rule out some weaker/more elevated
thunderstorms forming slightly behind it, but overall concern
for any severe storms in our southern CWA seems to have trended
down from yesterday afternoon`s forecast.

- Temperatures/winds/smoke potential:
The very leading edges of the cold front will enter our northern
zones over the next few/several hours, with this front then
steadily marching southward through the rest of our CWA over the
course of the day. It`s passage will be marked by the arrival of
initially northeasterly...but eventually more "true" northerly
breezes...not overly-strong but sustained speeds generally
around 15 MPH/gusts 20-25 MPH. There is always at least some
uncertainty in the temperature forecast depending on exact
frontal timing/amount of cloud cover etc. but ended up making
minimal change to previous forecast, aiming from only upper
60s-low 70s far north, to mainly mid-upper 70s central, to as
warm as 80s along and especially south of the KS border
(possibly even upper 80s mainly Rooks/Osborne counties). As
already touched on, HRRR smoke modeling and upstream obs over
the Dakotas (featuring some reduced visibility) are increasingly
suggestive that smoke will cause at least degree of air quality
issues this afternoon-tonight, and Nebraska state agencies will
be assessing today for any possible need for air quality
headlines.


-- THIS EVENING-OVERNIGHT:
Even if any thunderstorms do clip our southern counties early
this evening, have maintained a dry forecast 7 PM and beyond, as
forcing quickly departs and instability (even elevated) steadily
departs southward. Confidence is high in a tranquil overnight
with light/variable winds under a surface high pressure regime.
The main question mark is cloud cover, as although lower clouds
(and possible fog potential) should vacate to slightly west of
our CWA, some mid-high level clouds will probably spill in from
the northwest. The amount of clouds (or lack thereof) will
certainly play a role in how cool it gets tonight, but we`re
currently aiming for a range from mid-upper 40s north/east...to
low-mid 50s elsewhere.


-- THURSDAY DAYTIME:
Confidence remains fairly high in a dry daytime (at least
through 7 PM), with only some degree of cloud cover (potentially
ower-level) working back eastward across the CWA as breezes turn
south-southwesterly at 10-15 MPH. This will result in a
quick/brief warm-up, with highs aimed from mid-upper 70s east to
low-mid west (perhaps upper 80s far southwest/Furnas County
area). Surface wildfire smoke could still be hanging around, but
the southerly breezes should at least temporarily mix it out
somewhat.


-- THURSDAY EVENING-OVERNIGHT:
All eyes will be on the next/secondary cold front that will dive
southward through our area...driven by another upper trough
tracking out of Canada toward the Upper Great Lakes/Midwest. By
far the main question at this point is: just how likely is
thunderstorm development/coverage over our CWA? This time frame
is toward the outer hours of higher-res models, with the HRRR
showing a distinct lack of activity over our CWA at least
through Midnight, while the NAMNest is more aggressive...firing
up scattered thunderstorms (a few possibly
strong/severe?)...especially within the southern half of our
CWA. Given the inherent uncertainty, rain/storm chances (PoPs)
have been kept fairly low, but have expanded somewhat in area.
How much elevated instability there will be to work with is
still in question (largely dependent on frontal timing/speed),
but IF this front trends any slower would not be surprised to
see SPC "upgrade" to a Marginal Risk for especially parts of our
south, as the NAM is suggesting decent CAPE on the order of
1000-2000 J/kg. Low temps should be fairly similar to
tonight...with most areas low-mid 50s.


-- FRIDAY-SUNDAY:
Although mainly Friday morning could feature some lingering
showers mainly in our southern CWA, overall this looks like a
dry and fairly spectacular stretch of weather (especially for
those who love early fall conditions). High temps Friday are
only expected to reach the upper 60s most areas, and assuming
clear/mostly clear skies, Friday night lows should drop into at
least the mid-upper 40s CWA-wide (likely marking the chilliest
night in several months). Saturday-Sunday should be a touch
warmer than Friday, but still only low-mid 70s for highs.


- MONDAY-TUESDAY:
Southerly breezes will bring back a return of a bit more
humidity and slightly warmer temperatures (highs mainly mid-
upper 70s). Various, low-confidence rain/thunderstorm chances
also enter the picture as some instability returns, but as it
currently stands most places should be dry most of the time (no
widespread storm chances evident).

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 631 AM CDT Wed Sep 3 2025

For KGRI/KEAR Airports:
- General overview:
High confidence in VFR ceiling/visibility and precipitation-free
conditions through the majority of the period. However, a few
spotty showers cannot be ruled out mainly this morning, and of
greater concern are: 1) The possibility for perhaps few hours of
MVFR ceiling this afternoon...2) The possibility for smoke from
Canada fires to reduce visibility to at least low-end VFR
(perhaps MVFR?) by this evening-overnight. Winds will not be a
significant issue, but a directional shift to northeasterly-
then-northerly will occur today behind a passing cold front,
with several hours of gusts at least 15-20KT likely.

- Ceiling/visibility/precipitation details:
High confidence in continued VFR through these first 6 hours,
although a few passing showers/sprinkles are possible this
morning. Considered introducing a PROB30 group for this
potential, but opted to acknowledge with a generic "vicinity
shower" group (thunderstorms appear unlikely). By the 18-00Z
time frame, it is likely that at least a low-end VFR ceiling
will arrive for several hours...possibly dropping into MVFR for
a time. Again strongly considered a TEMPO for MVFR ceiling, but
with consensus of most model guidance more suggestive of low-end
VFR will just continue to "hint" at MVFR possibility with SCT020
group.

By around 00Z any possible MVFR ceiling concerns should be
departed off to the south-southwest, but by then the next
potential concern arrives in the form of some degree of reduced
visibility from Canada wildfire smoke. Based on current obs
upstream over SD, at least low-end VFR visibility seems fairly
likely, and MVFR is certainly possible. Given the inherent
uncertainty with smoke concentrations especially beyond 6-12
hours, have opted to maintain low-end VFR in a "6SM FU" group.

- Wind details:
Winds these first few hours will remain light but exhibit
varying direction trending from more westerly to north-
northeasterly behind the leading edges of a passing cold front.
Once this frontal passage occurs by around 15Z a few hours of
steady northeast breezes around 10KT will be followed by a
transition to more "true" northerly winds by mid-late afternoon
along with some modest breeziness (sustained speeds at least
10-13KT/gusts 15-20KT and perhaps briefly higher). Wind speeds
will steadily diminish by around and especially after sunset,
with a light/variable direction regime prevailing through the
overnight.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.

&&

$$

DISCUSSION...Pfannkuch
AVIATION...Pfannkuch