Alert archive / Wyoming / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 271, NWS Cheyenne, WY

August 1, 2025Goshen County, Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 1, 2025, 5:00 PM MDT for Goshen County, Laramie County, Wyoming. It was in force for 45 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 1, 2025, 5:00 PM MDT (23:00 UTC)
Expired: Aug 1, 2025, 5:45 PM MDT
In force: 45 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Goshen County, WY, Laramie County, WY

The radar

The Cheyenne radar (KCYS), 65 km from the middle of the area, began a volume at 23:00 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 1, 2:46 PM MDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 11.0 hours before the alert went out and 353 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 224 J/kg
Mixed-layer CIN: -449 J/kg
Mixed-layer LCL: 1557 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 123 m²/s²
0-3 km storm-relative helicity: 122 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Aug 1, 2:33 PM MDT, 2 hours 27 minutes earlier.

Area forecast discussion, Aug 1, 2:33 PM MDT, 2 hours 27 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Hazardous weather outlook, Aug 1, 2:34 PM MDT, 2 hours 26 minutes before

Hazardous Weather Outlook
National Weather Service Cheyenne WY
234 PM MDT Fri Aug 1 2025

NEZ002-003-019>021-054-055-095-096-WYZ101>119-022045-
Dawes County-Box Butte County-Scotts Bluff County-Banner County-
Morrill County-Kimball County-Cheyenne County-
Northern Sioux County-Southern Sioux County-
Converse County Lower Elevations-Niobrara County-
North Laramie Range-Ferris/Seminoe/Shirley Mountains-
Shirley Basin-Central Laramie Range and Southwest Platte County-
East Platte County-Goshen County-Central Carbon County-
North Snowy Range Foothills-Southwest Carbon County-
Sierra Madre Range-Upper North Platte River Basin-Snowy Range-
Laramie Valley-South Laramie Range-South Laramie Range Foothills-
Central Laramie County-East Laramie County-
234 PM MDT Fri Aug 1 2025

This hazardous weather outlook is for portions of panhandle
Nebraska...east central Wyoming...south central Wyoming and
southeast Wyoming.

.DAY ONE...THIS AFTERNOON AND TONIGHT

- There is a Slight Risk (Level 2 of 5) for severe weather
  Friday afternoon and evening east of the Laramie Range. All
  modes of severe weather are possible: hail, winds, tornadoes,
  and flash flooding.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

- There is a Marginal Risk of severe weather for Saturday,
  mainly across western Nebraska. Primary hazards look to be
  hail, wind, and flash flooding.

- Drier and warmer conditions return mid-week and continue
  through the weekend.

.Spotter information statement...

Spotter reports for severe weather and heavy rainfall are
encouraged.

In the hours before

Special weather statement, Aug 1, 2:09 PM MDT, 2 hours 51 minutes before

Special Weather Statement
National Weather Service Cheyenne WY
209 PM MDT Fri Aug 1 2025

WYZ103-105-106-115-012045-
Shirley Basin WY-
Central Laramie Range and Southwest Platte County WY-
North Laramie Range WY-Laramie Valley WY-
209 PM MDT Fri Aug 1 2025

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL ALBANY COUNTY
THROUGH 245 PM MDT...

At 209 PM MDT, Doppler radar was tracking a strong thunderstorm near
Wheatland Reservoir Number 3, or 37 miles north of Laramie, moving
east at 15 mph.

HAZARD...Wind gusts up to 50 mph and nickel 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...
Sybille Canyon, Wheatland Reservoir Number 3, and Flying X Ranch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4175 10574 4193 10575 4199 10533 4172 10531
TIME...MOT...LOC 2009Z 267DEG 12KT 4185 10565

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...50 MPH

MM

Special weather statement, Aug 1, 4:30 PM MDT, 30 minutes before

Special Weather Statement
National Weather Service Cheyenne WY
430 PM MDT Fri Aug 1 2025

WYZ117-118-012300-
Central Laramie County WY-South Laramie Range Foothills WY-
430 PM MDT Fri Aug 1 2025

...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN LARAMIE COUNTY
THROUGH 500 PM MDT...

At 430 PM MDT, Doppler radar was tracking a strong thunderstorm over
Rocking Star Ranch, or 12 miles northwest of Cheyenne, moving east at
10 mph.

HAZARD...Wind gusts up to 40 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...
Cheyenne, Happy Valley, Federal, Rocking Star Ranch, Silver Sage
Estates, Ranchettes, Cheyenne Regional Airport, Warren AFB, Frontier
Park, North Cheyenne, and Fox Farm-College.

This includes Interstate 25 in Wyoming between mile markers 11 and
27.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Tornado Watch remains in effect until 1000 PM MDT for southeastern
Wyoming.

&&

LAT...LON 4113 10510 4130 10513 4139 10481 4113 10475
TIME...MOT...LOC 2230Z 258DEG 8KT 4124 10499

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

KM

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 31, 6:02 PM MDT	Special Weather Statement	CYS	Goshen	28 min
Jul 31, 6:47 PM MDT	Special Weather Statement	CYS	Niobrara	28 min
Aug 1, 2:09 PM MDT	Special Weather Statement	CYS	Albany	36 min
Aug 1, 3:08 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	20 min
Aug 1, 4:30 PM MDT	Special Weather Statement	CYS	Laramie	30 min
Aug 1, 4:52 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie	38 min
Aug 1, 5:09 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	51 min
Aug 1, 5:30 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	45 min
Aug 1, 5:42 PM MDT	Tornado Warning	CYS	Laramie	33 min
Aug 1, 5:50 PM MDT	Areal Flood Advisory	CYS	Laramie	115 min
Jul 31, 6:14 PM MDT	Special Weather Statement	CYS	Banner, Kimball, Scotts Bluff	31 min
Jul 31, 6:17 PM MDT	Special Weather Statement	CYS	Scotts Bluff	28 min
Jul 31, 6:30 PM MDT	Special Weather Statement	CYS	Sioux	30 min
Jul 31, 6:35 PM MDT	Special Weather Statement	CYS	Sioux	25 min
Jul 31, 6:47 PM MDT	Special Weather Statement	CYS	Cheyenne, Scotts Bluff	43 min
Jul 31, 7:00 PM MDT	Special Weather Statement	CYS	Sioux	30 min
Jul 31, 7:35 PM MDT	Special Weather Statement	CYS	Sioux	25 min
Jul 31, 7:50 PM MDT	Special Weather Statement	CYS	Box Butte	25 min
Jul 31, 7:59 PM MDT	Special Weather Statement	CYS	Dawes	46 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2025 Every severe thunderstorm warning in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.