What forecasters said that day
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Cheyenne, WY wrote its last area forecast discussion before the first event at May 3, 1:16 PM MST, 2 hours 26 minutes earlier. Its key messages:
- Widely scattered showers and isolated thunderstorms are expected this afternoon and evening, and may produce gusty and erratic winds.
- An powerful cold front arriving Monday will bring a chance for showers and thunderstorms, changing over to snow Monday night and continuing into Wednesday morning.
- Accumulating snowfall is likely (70% chance) over 6000 feet in elevation, with significant snowfall possible in the Snowy Range, southern Laramie Range, and their adjacent foothills.
- Drier, warmer, and windier weather returns to the area for the second half of the work week.
Area forecast discussion, May 3, 1:16 PM MST, 2 hours 26 minutes before
Area Forecast Discussion
National Weather Service Cheyenne WY
216 PM MDT Sun May 3 2026
.KEY MESSAGES...
- Widely scattered showers and isolated thunderstorms are
expected this afternoon and evening, and may produce gusty and
erratic winds.
- An powerful cold front arriving Monday will bring a chance
for showers and thunderstorms, changing over to snow Monday
night and continuing into Wednesday morning.
- Accumulating snowfall is likely (70% chance) over 6000 feet in
elevation, with significant snowfall possible in the Snowy
Range, southern Laramie Range, and their adjacent foothills.
- Drier, warmer, and windier weather returns to the area for the
second half of the work week.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 216 PM MDT Sun May 3 2026
Now: Some storms are popping up across Campbell county and are
slowly dipping south into Converse and Niobrara county. These storms
are currently producing lightning with some rain possibly hitting
the ground but would still need to watch out for any fires started
by dry lightning. There are also a couple showers that is producing
mostly virga with a couple spits of rain in Central Laramie County
and crossing the Colorado border. The HREF shows some modest CAPE
that these storms could utilize along the Northern border of our
forecast area.
Monday and Tuesday: A cold front will push through Monday morning to
kick off some rain showers in the early afternoon. The surface cold
front is expected to pass through during the day. This may reach
Douglas to Chadron by 7AM or so, stunting high temperatures there
for the day. The front should reach the I-80 corridor by midday. As
a result, expect most areas to see a morning or early afternoon high
temperature, with gradual cooling through the afternoon hours. After
sunset, temperatures will begin to rapidly cool. The surface front
will slow down as it pushes up against the higher terrain of
southern Wyoming and northern Colorado, leading to frontogenesis.
Forecast soundings along the I- 80 corridor Monday afternoon look
nearly saturated with fairly steep lapse rates in place. SBCAPE
could locally exceed 1000 J/kg. Strong forcing provided by the
frontogenesis and moderate overrunning flow should kick off numerous
showers and scattered thunderstorms around midday Monday, mostly
along the I-80 corridor. A few stronger storms capable of producing
hail and gusty winds cannot be ruled out. By the evening into the
overnight hours the rain will transition to snow across the southern
half of the forecast area. The mountains will likely transition into
snow the quickest due to the higher elevation. The lower elevations
are expected to switch a lot slower leading to more of a rain/snow
mix through the overnight period. Majority of model guidance depicts
strong a strong band of FGEN with some isentropic lift to increase
the precipitation rates and lead to greater accumulations. The LREF
shows a 25/75th percentile of 3 to 8 inches of snow for Central
Laramie county and between 5 to 11 inches for the foothills/summit
area. Due to the favorable upslope flow the Snowy range could see
between 13 to 18 inches depending on elevation. The models also show
the band of FGEN to be pretty progressive through our area, however
the mountains may hinder it some leading to possibly higher amounts
on the mountain. The Sierra Madres are expected to be mostly
shadowed by the Snowies this event so up to 6 inches is expected for
that range. Since Laramie also sits in bowl, there's also some
potentially shadowing for the town as well leading to lower
accumulations than the rest of the area. Accumulations will also
depend on the timing, as snow falling during the day will be much
less likely to stick and accumulating thanks to the very strong
early May sun. We will therefore wait a little longer for confidence
to improve before including lower elevation zones in any winter
weather headlines. However, if this plays out like the models are
anticipating then an Advisory or a winter storm warning may be
needed for the lower elevations in the mountains and also possibly
for Laramie county as well.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Issued at 410 AM MDT Sun May 3 2026
Strong ridging will try to build back into the western US
immediately after this storm system. While Wednesday will still
feature temperatures well below average for this time of year,
expect warmth to recover quickly. Highs around 5F above average can
be expected on Thursday, climbing closer to 10F above average by
Saturday. Northwest flow will kick up quickly behind the departing
trough axis on Wednesday, and lead to breezy to windy conditions.
The strongest winds are anticipated on Thursday, when the southeast
Wyoming wind prone areas continue to have a 20 to 40% chance for
high winds. Both Thursday and Friday will feature isolated to widely
scattered PM showers and perhaps a few thunderstorms, but rainfall
expectations are limited at best. Precipitation potential will tick
up over the weekend a progressive upper level low approaches the
area from the northwest. The details concerning this system remain
highly uncertain at this lead time.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1140 AM MDT Sun May 3 2026
VFR conditions are expected through the remainder of the
afternoon, except during thunderstorms. Daytime heating paired
with a shortwave moving in from the northwest is promoting
cumulus development over the mountain ranges, ceilings around
8.5-10 kft. This activity is expected to increase in coverage
and lead to the formation of showers and thunderstorms this
afternoon, particularly for KCDR, KBFF, and KAIA. Elected to
include KRWL in a PROB30 thunderstorm group given some model
support. Coverage is not expected to be widespread, therefore
PROB30 groups were left in the 18z TAFS. Any convective shower
or thunderstorm runs the risk of producing strong, variable
surface winds, lightning, reduced visibility, and turbulence.
Activity is expected to begin around 20z and persist until 03z.
Overnight a cold front will move in shifting winds from the
north and lowering ceilings at terminals. At the end of the
forecast period rain chances begin to increase at Wyoming
terminals.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Winter Storm Watch from Monday evening through Wednesday
morning for WYZ110-114-116-117.
Red Flag Warning until 8 PM MDT this evening for WYZ430-431.
NE...None.
&&
SHORT TERM...MM
LONG TERM...MN
AVIATION...RVIn the hours before
Special weather statement, May 3, 1:30 PM MST, 2 hours 12 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
230 PM MDT Sun May 3 2026
WYZ101-102-032115-
Converse County Lower Elevations WY-Niobrara County WY-
230 PM MDT Sun May 3 2026
...STRONG THUNDERSTORMS WILL IMPACT SOUTHWESTERN NIOBRARA AND EASTERN
CONVERSE COUNTIES THROUGH 315 PM MDT...
At 230 PM MDT, Doppler radar was tracking a cluster of strong
thunderstorms near Manning Ranch, or 32 miles northwest of Lusk,
moving southeast at 35 mph.
HAZARD...Wind gusts up to 40 mph and pea 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...
Lance Creek and Manning Ranch.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4307 10509 4323 10491 4299 10441 4277 10474
TIME...MOT...LOC 2030Z 310DEG 29KT 4309 10493
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH
VasquezSpecial weather statement, May 3, 1:49 PM MST, 1 hour 53 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
249 PM MDT Sun May 3 2026
WYZ102-032115-
Niobrara County WY-
249 PM MDT Sun May 3 2026
...STRONG THUNDERSTORMS WILL IMPACT NORTHEASTERN NIOBRARA COUNTY
THROUGH 315 PM MDT...
At 249 PM MDT, Doppler radar was tracking a cluster of strong
thunderstorms 9 miles northwest of Redbird, or 30 miles west of
Edgemont, moving southeast at 30 mph.
HAZARD...Wind gusts up to 40 mph and pea 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...
Mule Creek Junction and Redbird.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4332 10406 4328 10405 4306 10421 4328 10461
4350 10441 4350 10406
TIME...MOT...LOC 2049Z 303DEG 25KT 4333 10442
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH
VasquezSpecial weather statement, May 3, 2:57 PM MST, 45 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
357 PM MDT Sun May 3 2026
NEZ002-095-WYZ102-108-032230-
Dawes NE-North Sioux NE-Goshen County WY-Niobrara County WY-
357 PM MDT Sun May 3 2026
...STRONG THUNDERSTORMS WILL IMPACT WESTERN DAWES...NORTHERN SIOUX...
SOUTHEASTERN NIOBRARA AND NORTHEASTERN GOSHEN COUNTIES THROUGH 430 PM
MDT...
At 357 PM MDT, Doppler radar was tracking a cluster of strong
thunderstorms along a line extending from 10 miles east of Rumford to
near Montrose to near Van Tassell. Movement was southeast at 45 mph.
HAZARD...Wind gusts up to 50 mph and pea 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, Harrison, Whitney, Van Tassell, Chadron Municipal Airport,
Whitney Lake, Soldier Creek Campground, Montrose, Fort Robinson State
Park, Agate Fossil Beds National Monument, Toadstool Geological Park
and Campground, and Belmont.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4261 10321 4244 10348 4243 10410 4262 10423
4300 10405 4300 10300
TIME...MOT...LOC 2157Z 308DEG 37KT 4317 10351 4290 10371 4264 10406
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH
VasquezLocal storm report, May 3, 3:03 PM MST, 39 minutes before
Preliminary Local Storm Report
National Weather Service Cheyenne WY
403 PM MDT Sun May 3 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0346 PM Tstm Wnd Gst 3 W Van Tassell 42.67N 104.16W
05/03/2026 M58 MPH Niobrara WY Mesonet
Mesonet station WY60 3.4 W Van Tassell
(WYDOT). 20dBZ convective shower over Van
Tassell gusted 58mph.
&&Special weather statement, May 3, 3:28 PM MST, 14 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
428 PM MDT Sun May 3 2026
NEZ002-095-032300-
Dawes NE-North Sioux NE-
428 PM MDT Sun May 3 2026
...STRONG THUNDERSTORMS WILL IMPACT DAWES AND EAST CENTRAL SIOUX
COUNTIES THROUGH 500 PM MDT...
At 428 PM MDT, Doppler radar was tracking a cluster of strong
thunderstorms along a line extending from 12 miles northwest of
Chadron Municipal Airport to near Whitney to near Crawford. Movement
was east at 45 mph.
HAZARD...Wind gusts up to 50 mph and pea 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...
Chadron, Crawford, Whitney, Roberts Trailhead Campground, Chadron
Municipal Airport, Chadron State Park, Whitney Lake, Soldier Creek
Campground, Red Cloud Campground, Fort Robinson State Park, Dawes
County Fairgrounds, and Chadron State Park Campground.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4262 10352 4300 10338 4300 10279 4279 10279
4278 10277 4274 10277 4248 10278
TIME...MOT...LOC 2228Z 278DEG 41KT 4299 10322 4283 10321 4264 10339
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH
Vasquez