Alton, Kansas Weather Forecast Discussion

812
FXUS63 KGID 142359
AFDGID
Area Forecast Discussion
National Weather Service Hastings NE
659 PM CDT Sun Sep 14 2025
...Aviation Update...
.KEY MESSAGES...
- A Severe Thunderstorm Watch remains in effect for most of our
  forecast area through 10 PM. Large hail/damaging winds look
  to be the main threat.
- Forecast dries out after midnight tonight, and remains dry
  through Monday night. Highs on Monday look to reach into the
  80s.
- An area of low pressure slowly moving in from the NW and then
  sticking around through the end of the week keeps
  preciptiation chances in the forecast Tuesday-Saturday. The
  overall best chances are in the Tuesday evening-Wednesday
  night time frame with the system`s initial arrival. Some
  strong-severe storms are not out of the question Tue-Tue
  night.
- Highs on Tuesday are once again in the 80s, with highs the
  rest of the week back in the 70s with the precipitation
  chances lingering in the forecast.
&&
.DISCUSSION...
Issued at 351 PM CDT Sun Sep 14 2025
Currently through tonight...
Showers and storms are riding along both the western and eastern
fringes of the forecast area this afternoon...and especially for
western areas, that threat will continue to increase the rest
of this afternoon/evening. Looking aloft, upper air and
satellite data showing an area of low pressure set up over
western NE...making only a little ENEward progress thanks to a
well amplified ridge of high pressure extending north from the
western Gulf Coast into the western Great Lakes. At the surface,
the forecast area has been sitting under increasing SSErly
winds, east of the main frontal boundary while lies across
western portions of KS/NE into the Dakotas. It`s taken a while
for speeds to pick up, partly due to the plentiful cloud cover
that had been in place...seeing more gusts around 20-25 MPH,
especially across the western half of the forecast area. The day
started out with overcast skies for most locations, and though
that mid-upper level cloud cover has been pushing further east
with time, lower level CU has been filling in behind...so even
now most spots are still at least partly cloudy. Even with the
clouds lingering around, by the time it`s all said and done,
highs don`t look to end up working out too bad...most spots are
in the mid- upper 70s.
As far as storm chances go...the activity currently along our
eastern fringe is expected to continue pushing ENE the rest of
this afternoon, with our main focus turning to areas just off
to our west. This activity is tied closer to the main upper
level low/trough...and models remain in fairly good agreement
showing the current cluster running roughly from BBW
southwestward to GLD continuing on an eastward march in the
coming hours. SPC mesoanalysis page continues to show that the
main axis of instability (MLCAPE values around 1500 j/kg) lying
through the western portions of our forecast area, where there
has been more sun...but the main axis of better deeper layer
shear around 40kts is offset from that a bit, more centered
through the eastern portions of the forecast area. That being
said...while not ideally lined up, there is sufficient
overlapping that any storm that impacts the forecast area will
have the potential to be strong- severe...especially over
western areas where along with the instability, lapse rates are
better...and the SPC Day 1 Slight/Marginal Risk areas have
remained unchanged through the day.
This threat will continue on through the evening hours...with
models showing the strength and overall coverage diminishing
as the upper level forcing makes more of a northward push and
with the loss of daytime heating. Kept a slight chance (20
percent) of precipitation going through just after midnight,
then the rest of the night looks dry.
Monday...
Overall no notable changes were made to the forecast for the
first day of the new work week...which remains dry. Models
continue to show a messy, blocked pattern across the CONUS...low
pressure remains anchored over the SErn CONUS, with a couple
areas of low pressure over the north central Plains through the
Pac NW...with ridging sandwiched in between. Winds remain
southerly around 10-15 MPH...highs climbing into the mid-80s for
most.
Tuesday on through the week...
The weather for the rest of the week will continue to be driven
by an even slower than usual moving upper level
pattern...keeping plenty of chances for preciptiation around the
region. Models are in generally good agreement looking at the
bigger picture...showing the upper level energy currently in the
Pac NW region eventually pushing further ESE into the local
area around the Wed-Thu time frame, but then makes little effort
to push out of the Plains through the rest of the week. The
overall best chances for storms are tied to its initial arrival
late Tue, more Tue night-Wed night...with chances more scattered
and having lower overall confidence Thursday and on. Potential
for some strong-severe storms remains Tue-Tue night...with most
of the forecast area remaining in the SPC Day 3 Marginal Risk
area.
As far as temperatures go, plenty of 80s look to linger on into
Tuesday...dropping back into the 70s Wed-Sat, tied to those
additional precip chances in the forecast.
&&
.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 658 PM CDT Sun Sep 14 2025
For KGRI/KEAR Airports:
- General overview (including winds):
High confidence in VFR ceiling/visibility through the vast
majority of the period. However, the two main exceptions are:
1) Right away these first few hours as a band of strong
thunderstorms pushes through from west-to-east...2) For at
least a few (possibly several?) hours very late tonight into Mon
AM if low clouds and/or fog manage to create sub-VFR
conditions. Outside of any near-term convective outflow, winds
will not be a significant issue, with sustained speeds at-or-
below 10KT from mainly a southerly direction through much of the
period, except for sporadic gusts as high as 15-20KT both right
away this evening ahead of the convective line and also Monday
afternoon.
- Thunderstorm/precipitation details:
Truly the ONLY concern is right away this evening, with a fairly
narrow line of strong storms right on the doorstep of KEAR here
at 00Z, and this line likely to reach KGRI between 01-02Z. Have
covered this fairly brief window of shower/thunderstorm
potential with TEMPO groups (00-02Z KEAR/01-03Z KGRI).
Fortunately, these storms have struggled to reach severe levels,
but at least brief/erratic gusts to at least 30KT are likely. In
brief heavy rain (and possibly small hail), visibility and/or
ceiling will likely drop to MVFR/IFR levels briefly.
- Ceiling/visibility details (beyond evening thunderstorms):
The main question mark (and unfortunately still not a very clear
one) is whether or not a few-to-several hours of low clouds
and/or fog develops early Monday morning in the wake of
departing convection? Admittedly, latest models/guidance are
kind of "all over the place" on this potential right now, so in
prevailing groups have maintained VFR while "hinting" of sub-VFR
potential. However, DID decide to introduce a medium-confidence
TEMPO centered 10-14Z for at least brief/sporadic sub-VFR
conditions (potentially at least IFR ceiling/visibility). This
will bear close watching as it draws closer in time and
hopefully confidence-in-occurrence increases/decreases.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
DISCUSSION...ADP
AVIATION...Pfannkuch

NWS GID Office Area Forecast Discussion