Hail in Nebraska, June 28, 2026

Area Forecast Discussion
National Weather Service Cheyenne WY
1122 PM MDT Sun Jun 28 2026

.KEY MESSAGES...

- A few evening and overnight showers and thunderstorms are
  possible over the High Plains, mainly north of the North
  Platte River.

- Southwest winds will increase Monday, bringing the potential
  for critical fire weather conditions over the High Plains and
  a brief period of high winds in the wind prone areas.

- Elevated fire weather conditions will continue for much of
  the week ahead.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 315 PM MDT Sun Jun 28 2026

A sprawling, unseasonably strong upper level low continues to
circulate over the northern Rockies this afternoon. Southwest flow
continues aloft with dry air moving in from the desert areas.
Temperatures are a little cooler across the area compared to
yesterday, generally in the upper 70s to 80s for most. Breezy
conditions are also continuing, but again, winds are less strong
than yesterday.

This will become a bit more interesting tonight. A surface high
pressure system is moving into western Wyoming, with a boundary
currently stalled roughly from Medicine Bow Peak towards the
southwest corner of South Dakota. Meanwhile, lee cyclogenesis is
occurring over northeast Colorado. This is expected to
strengthen rapidly this evening and then begin to eject
northeastward overnight. The surface cyclone is unusually strong
for summer. NAEFS mean MSLP is approaching the climatological
minimum this afternoon and evening. As this system strengthens,
it will pull the stalled boundary to the south and east,
ushering in a surge in northwest winds across the area
overnight. Expect most of the area to remain breezy to windy
overnight as a tight pressure gradient remains in place over the
plains. Meanwhile, a secondary vort-max rotating around the
primary upper level low will dig into the Great Basin, enhancing
southerly flow aloft on top of the developing surface cyclone.
The combination of overrunning warm air advection aloft and
potent low to mid level frontogenesis will support fairly strong
forcing for ascent overnight. Expect a few showers to develop
late afternoon into the evening along this boundary, mostly
inside/north of a Douglas to Wheatland to Chadron line. Elevated
instability will increase through the evening as low level
moisture recovers. Expect showers to have a bit more thunder as
the evening goes on. Scattered thunderstorm potential will
continue all through the night, winding down around sundown.
High resolution models are not in very good agreement on the
extent of this nocturnal activity, but PoPs in the 20 to 50%
range are maintained in our northeastern areas (Niobrara,
northern panhandle) due to the potent forcing. Models often
struggle to handle nocturnal elevated convection, and the large-
scale picture suggests this potential tonight even if high
resolution models don't all show this. In addition, look for
some shower activity moving into Carbon County overnight
associated with this system. Temperatures will be cool enough
that we can expect some snow mixing in about 9000 ft in
elevation or so. Those camping at high elevation tonight can
expect a chilly night with near freezing lows and perhaps a
dusting of snow by morning.

The aforementioned vort-max will swing through the area around
midday Monday. Expect a brief surge in low level height gradients
and 700-mb winds ahead of the boundary. Models have come into better
agreement on the wind forecast. Both the GFS and NAM have 700-mb
Craig to Casper height gradients peaking around 50 to 55 meters
between 15z and 18z Monday, which is supportive of marginally high
winds. Cross barrier MSLP gradients look good for high winds, but
the window is very short as this gradient is mainly associated with
a progressive frontal boundary following the vort-max aloft. So,
overall, expect winds to turn back to southwest and then rapidly
increase Monday morning, peak around noon, turn slightly more
westerly behind the frontal boundary early afternoon, and then
weaken through the remainder of the afternoon. This is pretty
much a toss-up for high winds, with in-house guidance showing
probabilities for high winds at 50% for Arlington and Bordeaux,
and 40% for the I- 80 summit. Probabilities around 30 to 40%
also extend to other areas adjacent to the typical wind prone
areas in Carbon, Converse, and Platte counties. While confidence
is fairly low, it is high enough at this time to at least
warrant a High Wind Watch for the wind prone areas. A brief
period with gusts of 60+mph may be possible in the adjacent
areas, but due to the short window and lower probabilities,
decided to hold off on including any of those areas in the
watch.

While hitting 60+mph is more uncertain, we do have high confidence
in a widespread breezy to windy day. Expect fairly widespread gusts
in the 40 to 50 mph range across the area. While temperatures will
be cooler, a very dry airmass will continue to filter into the area,
pushing RH to near critical values. South of the North Platte River,
RH should be easily critical, but winds will be a little lighter
here. Confidence in reaching critical RH values north of the North
Platte River is lower, but due to the strong expectation for winds,
the entire area was included in the Fire Weather Watch. Control
issues are likely with these winds, even if RH doesn't quite reach
criteria. Monday will bring little to no chance for thunderstorm
activity due to the very dry airmass overspreading the area.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 315 PM MDT Sun Jun 28 2026

Tuesday, The upper level low will be lifting off to
the east back into the Northern Plains and Canadian providences as a
strong ridge over the Midwest and Eastern Seaboard begin to build.
By the late evening on Tuesday another weak shortwave will push
through the Intermountain West following the parent low moving into
Manitoba. There will be a few lobes of vorticity to play with as
this wave moves through but it looks as though all the forcing and
shower potential may lie only in the Panhandle area. As we progress
past Tuesday we become stuck in Southwest flow on the front side of
this ridge. The warm, dry, but smokey air from the Desert southwest
and the Colorado/Utah fires will be filtering over the area for the
remainder of the week. This will limit our rain chances as this dry
air removes all the moisture from the surface and lower dewpoints
and RH values. The models have a few shortwaves pushing into the
region past Tuesday but with no moisture and very limited forcing
there isn't much confidence these waves will do anything beside
increase our gradient and produce the normal amount of wind through
our area. Fire weather will be the biggest concern as our fuels will
enter a curing state once again despite our stormy 7 days last week.
Winds will be light to marginal so it may be difficult to reach Red
Flag criteria for most of our area despite the low RH and curing
fuels. There is a trough that is suppose to move through 4th of July
weekend that the models are trying to figure out so we may get some
rain but the Intermountain West would need a pretty big trough to
dig through the four corners region for anything substantial to
reach the ground. So we shall see how the models trend but the 4th
may just be as dry as the rest of the week as well.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1122 PM MDT Sun Jun 28 2026

VFR conditions will prevail for the duration of this TAF period.
Two things of aviation concern, showers and thunderstorms will
increase in coverage tonight across the Nebraska Panhandle where
KCDR is likely to be impacted at some point. Therefore, a PROB30
group remains for TS at KCDR due to the uncertainty in timing.
The other concern in this forecast period will be the drastic
uptick in winds through the early morning hours where gusts will
range between 30 and 45 knots. Strongest gusts can be expected
at KRWL, KLAR, KCYS, and KCDR.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Fire Weather Watch from 10 AM MDT Monday through Monday
     evening for WYZ417>419-430>433.
     High Wind Watch from 8 AM MDT Monday through Monday afternoon
     for WYZ106-110-116.
NE...Fire Weather Watch from 10 AM MDT Monday through Monday
     evening for NEZ434>437.

&&

SHORT TERM...MN
LONG TERM...MM
AVIATION...RZ

Special Weather Statement
National Weather Service Cheyenne WY
1027 PM MDT Sun Jun 28 2026

NEZ096-WYZ108-290500-
South Sioux NE-Goshen County WY-
1027 PM MDT Sun Jun 28 2026

...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN SIOUX AND EAST
CENTRAL GOSHEN COUNTIES THROUGH 1100 PM MDT...

At 1027 PM MDT, Doppler radar was tracking a strong thunderstorm 9
miles northeast of Henry, or 11 miles east of Torrington, moving
north at 30 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Agate Fossil Beds National Monument.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4205 10381 4202 10405 4242 10414 4242 10373
TIME...MOT...LOC 0427Z 170DEG 27KT 4212 10395

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Zawislak

Special Weather Statement
National Weather Service Cheyenne WY
1102 PM MDT Sun Jun 28 2026

NEZ002-003-095-096-290545-
Box Butte NE-Dawes NE-North Sioux NE-South Sioux NE-
1102 PM MDT Sun Jun 28 2026

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN BOX BUTTE...
SOUTHWESTERN DAWES AND SOUTHEASTERN SIOUX COUNTIES THROUGH 1145 PM
MDT...

At 1102 PM MDT, Doppler radar was tracking a strong thunderstorm near
Agate Fossil Beds National Monument, or 28 miles northeast of
Torrington, moving northeast at 40 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Crawford, Soldier Creek Campground, Agate Fossil Beds National
Monument, Fort Robinson State Park, Belmont, and the south fork burn
scar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4220 10371 4231 10389 4276 10351 4257 10308
TIME...MOT...LOC 0502Z 219DEG 36KT 4232 10374

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Trudel

Special Weather Statement
National Weather Service Cheyenne WY
1155 PM MDT Sun Jun 28 2026

NEZ095-096-WYZ102-108-290645-
North Sioux NE-South Sioux NE-Goshen County WY-Niobrara County WY-
1155 PM MDT Sun Jun 28 2026

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL SIOUX...SOUTHEASTERN
NIOBRARA AND NORTHEASTERN GOSHEN COUNTIES THROUGH 1245 AM MDT...

At 1155 PM MDT, Doppler radar was tracking a strong thunderstorm 12
miles southwest of Agate Fossil Beds National Monument, or 19 miles
northeast of Torrington, moving northeast at 40 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Harrison, Van Tassell, Agate Fossil Beds National Monument, and Fort
Robinson State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4221 10393 4226 10425 4275 10415 4269 10353
TIME...MOT...LOC 0555Z 204DEG 35KT 4232 10400

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Trudel