277
FXUS63 KGID 171221
AFDGID

Area Forecast Discussion
National Weather Service Hastings NE
721 AM CDT Tue Jun 17 2025

...Aviation Update...

.KEY MESSAGES...

- Another potential (but rather uncertain-in-the-details) risk
  of severe storms will focus MAINLY during the 5 PM-Midnight
  time frame, with our southern forecast area (CWA) appearing to
  be more "under the gun" than our northern areas. However, it`s
  also possible that ongoing/upcoming early-day convection
  COULD continue to shunt the overall-greater threat more-so
  south of our CWA altogether.

- In addition to the severe storm threat, at least LIMITED
  portions of our area will continue to need watched for mainly
  minor/short-term flooding issues, as various parts (but FAR
  from all) of our CWA saw at least 2-3" of rain (localized
  3-5") since Monday evening, with the potential there for
  another generally 1-2" during these next 24 hours.

- Getting beyond the shorter-term severe storm threat, BY FAR
  our main concern is what continues to look like the overall-
  hottest 3-day stretch of 2025-so-far centered Friday-Sunday,
  with widespread afternoon-early evening heat index readings of
  95-105 degrees (especially Fri-Sat), possibly prompting our
  first heat-related "headlines" of the year (although very
  breezy south winds will offer some relief to those outdoors).

&&

.DISCUSSION...
Issued at 605 AM CDT Tue Jun 17 2025

-- PRIMARY 7-DAY FORECAST BIG PICTURE THOUGHTS, CHANGES,
  UNCERTAINTIES:

- As evidenced by how late this discussion is going out the
  door this morning, it`s been a very busy night with limited
  time for "high end/deep-dive" forecast analysis.

- That being said, there really haven`t been any truly
  notable changes versus our going forecast messages of 12-24
  hours ago, with by far the main stories (severe threat next 18
  hours and late- week/weekend heat) clearly outlined in the KEY
  MESSAGES above.

- One relatively-minor change is that some low rain/non-severe
  thunderstorm chances (PoPs) have been expanded to more of our
  area (mainly eastern half) for Wednesday daytime for what
  should be fairly spotty/limited activity.

- While the vast majority of the Wednesday night-Sunday time
  frame will be marked by hot/dry weather, our next POTENTIALLY
  halfway-decent rain/thunderstorm chances could arrive about
  6-7 days from now (our forecast officially brings in these
  chances as early as Sunday night, but overall-better chances
  look to focus during the Mon-Tues time frame (obviously still
  plenty of uncertainty that far out).


-- 7-DAY FORECAST CHRONOLOGICAL BREAKDOWN (heavily focused first
 24 hours):
-- CURRENT/RECENT WEATHER SCENE AS OF 530 AM:
Honestly, the evening-overnight played out GENERALLY as
expected across our area, as intense thunderstorms indeed first
developed north and west of our CWA, then eventually moving
southward/eastward into our area while merging into a dizzying
array of lines/clusters that gradually moved thorugh much of our
area, prompting numerous reports of measured wind gusts into
the 50-70 MPH range (including in Grand Island/Hastings), and
with a handful of hail reports up to around quarter size
(fortunately a bit smaller than anticipated). Rainfall was
HIGHLY VARIABLE, ranging from well under one-half inch in some
places, to various narrow corridors and small-scale "bullseyes"
of at least 2-4" that caused at least some, mainly minor
flooding issues. Even outside the strongest storm cores,
"sneaky", mainly sub-severe wind gusts commonly reached at least
40-50 MPH due to a combination of "wake low" processes and in
at least one case (Lexington area) legitimate heat burst
activity (the dewpoint there plunged from 67 to 33 degrees
around the time a 77 MPH gust registered at the airport/LXN).

As of this writing, most of the northeast half of our CWA is
dry, while south-southwest areas are seeing mainly light
showers with some occasional transient heavier rain cores from
weak thunderstorm activity especially in Furnas/Phillips/Rooks
counties.

Winds vary considerably in direction/speed early this morning
(Still seeing some "random" gusts upwards of 20-30 MPH), while
morning low temps are ont rack to bottom out mainly low-mid 60s.

In the big picture of the mid-upper levels, water vapor
satellite imagery and short term model data confirm that we are
under quasi-zonal (generally west-east) flow aloft, as a low
amplitude shortwave trough is gradually approaching form the
Central Rockies.


- TODAY-TONIGHT:
Obviously our next potential severe storm threat is the main
focus. While the finer-scale details are far from clear, a heavy
lean toward the latest HRRR runs (which did a halfway-decent job
with the last 12 hours evolution) suggests that at least spotty,
mainly non-severe shower/thunderstorm activity could persist
much of the day...especially in our south...but cannot
"guarantee" completely dry anywhere so have at least baseline 20
percent/slight chances. The best chance for MOST of our CWA to
be dry is early-mid afternoon. However, by late afternoon/early
evening, the combo of lift from the slowly-deepening upper wave
arriving from the west, along with what should be a halfway
decent combo of mixed-layer CAPE mainly 1000-2000 J/kg (perhaps
2000-3000 J/kg in our far southern/KS zones) along with 30-50KT
of deep-layer shear could easily spark another round of severe
storms.

One potential POSITIVE NOTE versus 24 hours ago is that it`s
appearing increasingly likely that the main west-east corridor
of severe storms SHOULD now focus at least slightly south of our
CWA altogether...south of the large-scale outflow boundary
likely setting up near/south of I-70 (hence why SPC kept the
newly-introduced Level 4 Moderate Risk south of our area).
However, our far southern KS zones remain close enough to this
main instability axis to (at least for now) justify an Enhanced
Risk (Level 3), while MOST of our CWA is in either a Marginal
(level 1) or Slight (level 2) category. Because the vast
majority of our CWA will remain north of the main instability
axis/west-east zone of storm development, our MAIN concern will
be a generally north-south oriented line/cluster of storms
expected to march in from the west off the High Plains mainly
between 5 PM and Midnight. Just how robust this activity might
be is certainly in question, but at least sporadic gusts of
60-70 MPH, hail to around ping pong ball size, and MAYBE a brief
(mostly likely linear-embedded/QLCS) tornado cannot be totally
ruled out (mainly far south). We`ll also have to watch for at
least minor flooding issues in places that could see 1-2" in a
short time...especially if it tracks over some of the same
places that just saw at least 2-4" in the last 12 hours. Overall
though, hydro should not be a major concern for most of our
CWA.

Scattered showers/weaker storms will surely linger between
midnight-sunrise Wednesday, but even elevated instability will
really be on the decline, putting an end to any severe threat.

Confidence in high temps today is a little shaky as much will
depend on sky cover and how much (or how little?) daytime
convection develops, but for sure it will be noticeably cooler
than yesterday with highs currently aimed 78-83 for most of the
CWA. Wind direction will also likely be a bit "all over the
place" today, with southerly, westerly and even easterly
components possible before a more consistent northerly direction
arrives overnight behind the passing upper system and cold
front. Low temps tonight aimed a few degrees either side of 60.


- WEDNESDAY-WED NIGHT:
Although most of our CWA will be dry most of the day, especially
our eastern half to two-thirds could see spotty showers/weak
thunderstorms through much of the day (only 20% chances), with a
higher-confidence dry-area-wide forecast returning for Wed night
as upper ridging takes over as the dominant influence. High
temps seasonably-mild in the low-mid 80s, with lows again around
60. Daytime breezes out of the north-northwest.

- THURSDAY-THURS NIGHT:
While there are hints that storms could flirt with mainly our
far north Thurs late-day and overnight Thursday, our official
forecast remains dry as temperatures start to crank up, with
highs back into the low-mid 90s as winds flip back around to
southerly.

- FRIDAY-SUNDAY:
In short, HOT, dry and breezy-to-windy, as southerly winds gust
30+ MPH each day, pumping in heat as a large-scale ridge of
upper high pressure migrates from our south to our east. Actual
high temps mid-90s to low-100s, with heat index values currently
forecast to approach/reach Advisory criteria of 105 in various
areas (and more widespread 100-105). It will likely feel like a
slightly-humid "blast furnace" out there.

- SUN NIGHT-MONDAY:
A slight cool-down is currently expected, but that is not yet a
sure thing depending on how fast/slow the upper ridge vacates.
Still-highly-uncertain rain/thunderstorm chances start to
return.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 721 AM CDT Tue Jun 17 2025

For KGRI/KEAR Airports:
- For KGRI/KEAR Airports:
- General overview (including winds):
Although this is a fairly low confidence forecast with regard to
EXACT timing of potential shower/thunderstorm activity,
confidence is overall-high that at least the VAST MAJORITY of
the period will feature VFR ceiling/visibility and
dry/thunderstorm-free conditions. That being said, there appears
to be SOME potential for sub-VFR ceiling and possibly sub-VFR
visibility to develop especially late in the period tonight-
early Wed AM in the wake of departing convection. Even wind
direction/speeds are of unusually-low confidence especially
these first 12-18 hours, as the presence of convection and
various small-scale fronts/boundaries could promote winds from
almost any conceivable direction. That being said, winds today
are GENERALLY expected to prevail from southerly, westerly and
eventually easterly, with a more consistent north-northwesterly
direction kicking in overnight behind a cold front. Outside of
convective influences, speeds should mainly prevail at-or-below
12KT...BUT even right out of the gate this morning sporadic
30+KT gusts are occurring in the general area.


- Ceiling/thunderstorm/precipitation details and uncertainty:
Through most of the day today, spotty shower and perhaps weak
thunderstorm will occur, but with coverage expected to be
limited have handled mainly with basic "vicinity shower" (VCSH)
IF a more concentrated area of thunderstorm activity (perhaps
severe?) moves through the area it would most likely focus
between 23-05Z, so this is currently highlighted with a medium-
confidence PROB30 group. As if the first 12-18 hours doesn`t
feature enough uncertainty, the final 6 hours brings in another
possibility, mainly that of sub-VFR (MVFR/IFR) ceiling IF a low
stratus deck can become established. Although possible, this is
still considered low enough confidence that have maintained VFR
for now but "hinted" at possible sub-VFR with "SCT010" group".

&&

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

&&

$$

DISCUSSION...Pfannkuch
AVIATION...Pfannkuch