550
FXUS63 KGID 182147
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
447 PM CDT Tue Aug 18 2026

.KEY MESSAGES...

- Thunderstorm/severe weather potential tonight: Starting mainly
  after 9 PM and lasting through the rest of the overnight, our
  next round of at least scattered showers/thunderstorms will
  roll into our forecast area (CWA) mainly from the west-northwest,
  with a few storms perhaps strong to severe with a large
  hail/damaging wind threat.

- Ongoing flooding concerns mainly in the Mira Creek/community
  of North Loup area of southeastern Valley County: see separate
  "Hydrology" section below for more detail, but a Flood Warning
  continues for this small portion of our northern CWA.

- Still-highly-uncertain thunderstorm chances (and associated
  severe storm potential) Wed daytime-Thurs: Our "parade" of
  daily and/or nightly thunderstorm chances continue. However,
  upper level lift/forcing does not look quite as strong as
  tonight (or last night), casting some doubt on whether we`ll
  see much activity at all beyond lingering storms Wed AM. At
  least for now though, SPC has maintained a Marginal Risk of
  severe for our entire CWA Wed...and some northern counties
  Thurs.

- Additional storm chances beyond Thursday: Various/occasional
  rain/thunderstorm chances continue in this active weather
  pattern, but predictability in "finer details" will likely be
  "iffy" at best especially beyond 24 hours, so we need to take
  these chances mostly "one day at a time".

- Temperature overview next 7 days: an overall typical pattern
  for mid-late August...with highs most days in the 80s in our
  Nebraska zones...and more so low-mid 90s most days in
  Kansas...and lows most areas/most nights in the 60s. Wednesday
  currently looks like the overall coolest day (only upper
  70s-low 80s north)...Friday looking overall-warmest with mid-
  upper 80s most Nebraska...low-mid 90s KS and Furnas County
  area.

&&

.DISCUSSION...
Issued at 446 PM CDT Tue Aug 18 2026

-- FORECAST CHANGES OF NOTE/BIG PICTURE COMMENTS:
- No truly "notable" forecast changes worth discussing in
  detail, as we remain in a seasonably-warm and active weather
  pattern with various/intermittent rain/thunderstorm chances
  due to our region residing along the large-scale interface
  between large-scale upper high pressure/riding centered to our
  south- to-southwest...and broad troughing/low pressure
  centered to our north-to-northeast.

- In the "minor details" department, high temps have trended up
  slightly (at least a few degrees) for days such as Wednesday,
  Thursday and Monday as our tendency lately has been for highs
  to end up a bit warmer than forecasts from a few-to-several
  days out have called for.


-- 7-DAY FORECAST CHRONOLOGICAL RUNDOWN (through Tues. Aug. 25):
- CURRENT/RECENT WEATHER SCENE AS OF 345 PM:
In the wake of convection within mainly the northeast half of
our CWA Monday evening into early this morning that admittedly
"overachieved" in intensity and areal coverage (significant
wind damage/some hail damage in Ord area from intense supercell
pre- midnight...a more widespread area of damaging winds post-
midnight and even flooding rains in limited areas), fortunately
the bulk of today (and especially this afternoon) has been
"quiet/dry...as we reside "in between upper level
disturbances/shortwave troughs (the next one approaching from WY
per water vapor satellite/short term model data/analysis). At
the surface, winds have trended to a mainly light (under 10 MPH)
and variable direction regime.


- THIS EVENING-OVERNIGHT:
While MOST areas will remain dry/thunderstorm-free through at
least 9-10 PM (except for some spotty sprinkles/light showers
here or there), anytime after that is "fair game" for the
development of more widespread (at least scattered)
showers/thunderstorms as the aforementioned upper wave arrives
from the northwest and sparks at least (mainly) slighly-elevated
storms. Convective instability (CAPE) does not appear as high as
last night, but deep-layer shear will remain seasonably-strong
(at least 40-50KT), so at least a few strong to severe storms
appear possible. Admittedly, higher-res models runs (such as
from HRRR) from 24 hours ago did not verify well for last night,
but again leaning on the latest consensus of HRRR/NAMNest, the
first round of overnight convection should mainly focus into the
southern half of our CWA, as convection rolls in from the west
off the High Plains, while other storms developing along the
low-level frontal zone/along the exit region of the low level
jet (LLJ) MIGHT flirt with our eastern KS zones
(Jewell/Mitchell), but SHOULD mainly affect areas near the KS/NE
border slightly east of our CWA. Then, very late in the night
(mainly 4-7 AM), high-res models are hinting at a secondary area
of strong/severe storms developing into our northern CWA (north
of I-80) out of northern NE.

Low temps tonight mainly 60s, as breezes remain fairly light
but mainly trend more northerly.


- WEDNESDAY DAYTIME-EVENING (pre-midnight):
Honestly, our potentially biggest (and obviously first) concern
could be right away in the morning mainly 7-10 AM, as the
aforementioned potential cluster of strong/severe storms in our
northern CWA rides into our eastern counties (somewhat similar
to this morning, albeit later in the morning). Whether or not
this unfolds, from mid-morning onward through late afternoon
MOST of our CWA should remain dry as the upper wave passes by
(similar to today). That being said, very intentionally left at
least slight chances (20%) for spotty convection going for the
majority of the CWA through the entire day and into the evening,
in case any convection redevelops on the backside of departing
activity, and/or spotty new (and potentially supercellular)
development occurs during peak heating. Fortunately, high-res
models show any late afternoon-evening severe storm potential
being VERY isolated in the wake of departing upper forcing, but
cannot argue with SPC maintaining a broad Marginal Risk...just
in case.

Otherwise during the day Wednesday, high temps were nudged up
slightly, but this still looks like the overall-coolest day of
the next week most areas...ranging upper 70s-low 80s north...to
mid-upper 80s in KS and Furnas County area. Breezes mainly under
10 MPH and northerly to easterly.


- WEDNESDAY LATE NIGHT (post-midnight):
Fortunately, we should (in theory) catch a break from any late-
night/early AM convection for a change, as most models are
outright-dry and our official forecast follows suit. Depending
on sky cover/clearing trends, this could be a night to watch for
fog potential. Low temps mainly low-60s (one of our coolest
nights upcoming).


- THURSDAY-THURS NIGHT:
The daytime looks mainly dry, but the late afternoon into the
overnight carries at least small rain/thunderstorm chances
arrive with the next subtle disturbance dropping in from the
north-northwest. Like Wednesday late afternoon-evening, coverage
of storms looks very sparse, but at least for now SPC has
maintained a Marginal Risk for some of our northern-most
counties. High temps are aimed roughly 5 degrees warmer than
Wednesday...mid 80s most Nebraska counties...more so upper
80s-low 90s in KS and Furnas County area. Lows Thurs night not
quite as cool...mainly back up into mid 60s.


- FRIDAY-SATURDAY:
Although details are quite murky already at this time range,
much the same continues with intermittent rain/storm chances.
Friday the overall-warmest day of the next week for most of our
CWA...mainly upper 80s Nebraska and low-mid 90s KS and Furnas
County area. Perhaps very slightly cooler Saturday.


- SUNDAY-TUESDAY:
Compared to preceding days, this time frame looks at least
slightly-less-active (especially Mon-Tues), but mainly slight
chances for showers/storms continue intermittently. Temps aimed
similarly all 3 days...highs mainly mid 80s most of our Nebraska
counties, and more so upper 80s-mid 90s near/south of the KS
border.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 110 PM CDT Tue Aug 18 2026

For KGRI/KEAR Airports:
- General overview (including winds):
High confidence in VFR conditions (both ceiling and
visibility)...along with rain/thunderstorm-free weather through
at least these first 6-8 hours. However, anytime thereafter at
least isolated/scattered showers and thunderstorms (possibly a
few stronger ones?) could occur mainly this evening-overnight,
but possibly lingering into the first part of Wednesday daytime.
During any storms, visibility could at least briefly reduce to
at least MVFR, while in the wake of these storms there is at
least a small chance for at least intermittent lower ceiling
(most favoring MVFR). Aside from any possible convective
outflow/enhancement, winds will not be a significant issue,
with speed throughout the vast majority of the period prevailing
at- or-below 7KT, as direction generally transitions from more
southerly right away this afternoon, to more easterly and
eventually northerly from later this afternoon through the end
of the period.

- Ceiling/visibility and thunderstorm potential details:
Starting with ceiling, although some scattered low-end VFR
clouds could occur this afternoon, confidence is high that IF
any sub-VFR ceiling were to occur...it would likely hold off
until at least 09-10Z...in the wake of the majority of overnight
shower/thunderstorm potential. However, confidence is lower than
50% that MVFR ceiling will actually occur, so have only "hinted"
at it in TAFs with scattered MVFR-level clouds. Visibility-wise,
any sub-VFR would mainly be associated with possible brief
heavier downpours overnight into Wed AM, although a touch of
light fog probably cannot be ruled out either a few hours either
side of sunrise if the low-levels are not "mixed up" enough from
convection.

Finally regarding shower/thunderstorm potential, confidence in
"exact details" is running rather low, but based on general
consensus of latest higher-res models have introduced basic
PROB30 groups focused 03-09Z KEAR/04-10Z KGRI for the most
favored windows for at least isolated/scattered activity passing
through the area. If a thunderstorm occurs, at least small
hail/gusty winds cannot be ruled out. Beyond the PROB30 groups,
at least spotty rain shower (and possibly weak thunderstorm)
potential could linger a few more hours, but for now have simply
introduced a generic "vicinity shower" group.

&&

.HYDROLOGY...
Issued at 410 PM CDT Tue Aug 18 2026

Over the last 24 hours, most of (roughly) the northeast 1/2 of our
CWA picked up at least 0.50-1.50" of rain, with more localized
pockets of at least 2-3" (the majority of which fell in portions of
Valley/Greeley/Howard/Nance/Merrick/northern Fillmore counties.

In MOST places, this rain fell with little-to-no flooding impacts.
However, the MAIN EXCEPTION was within a very narrow (only 3-5 mile
wide) stripe, oriented northwest to southeast from southeastern
Valley County into southwestern Nance County...where at least 3-5"
fell, causing mainly minor flooding of creeks/streams and likely
several rural gravel/dirt roads. Of greatest concern is the Mira
Creek basin in southeastern Valley County, where an automated gauge
near North Loup has exceeded minor Flood Stage for the first time
since 2019 (as of 345 PM, the stage was 9.61 feet and starting
to level off...flood stage is 9.0 ft). While flooding of low
lying areas near the creek is ongoing, concerns for more
impactful flooding...including to homes along the creek on the
north side of North Loup...would increase especially if it
happens to "make a run" toward 11 feet (this is Moderate flood
stage). Fortunately, our "best guess" at this point based on
experience and the amount/orientation of rain within the basin
(please note this gauge is not one for which we receive official
forecasts from the Missouri Basin River Forecast
Center/MBRFC)is that the creek should not rise beyond 10
ft...then begin a slow fall sometime later today or this
evening. However, this will need monitored closely. The existing
Flood Warning may very well need extended through tonight at
least for the immediate Mira Creek/town of North Loup area.
Unfortunately, there is an outside chance of at least a brief
round of additional heavy rain overnight into Wednesday morning,
which could obviously slow any fall in water levels that
hopefully commences before then.

&&

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

&&

$$

DISCUSSION...Pfannkuch
AVIATION...Pfannkuch
HYDROLOGY...Pfannkuch