Alert archive / Wyoming / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 336, NWS Cheyenne, WY

August 3, 2023Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 3, 2023, 3:39 PM MDT for Laramie County, Wyoming. It was in force for 51 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 3, 2023, 3:39 PM MDT (21:39 UTC)
Expired
Aug 3, 2023, 4:30 PM MDT
In force
51 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 20 km from the middle of the area, began a volume at 21:42 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.

IssuedProductOfficeLasted
Aug 3, 2:57 PM MDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 9.7 hours before the alert went out and 343 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-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2023-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 156 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 12:00Z on 2023-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 22 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
156 J/kg
Mixed-layer CIN
-148 J/kg
Mixed-layer LCL
944 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
63 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

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 3, 3:39 PM MDT, 0 minutes earlier.

Area forecast discussion, Aug 3, 3:39 PM MDT, 0 minutes before
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Hazardous weather outlook, Aug 3, 2:39 AM MDT, 13 hours before
Hazardous Weather Outlook
National Weather Service Cheyenne WY
239 AM MDT Thu Aug 3 2023

WYZ101-103>107-109>118-040845-
Converse County Lower Elevations-North Laramie Range-
Ferris/Seminoe/Shirley Mountains-Shirley Basin-
Central Laramie Range and Southwest Platte County-
East Platte 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-
239 AM MDT Thu Aug 3 2023

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

.DAY ONE...TODAY AND TONIGHT

Scattered to numerous showers, and scattered thunderstorms will
occur this afternoon and evening. A few of the storms along and
east of Interstate 25 will likely produce small hail and gusty
winds. Brief heavy rainfall may occur from some thunderstorms
north of a Wheatland to Torrington line.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

There is a chance of afternoon and evening thunderstorms Friday
through Monday, with lesser chances for Tuesday and Wednesday.

.Spotter information statement...

Spotter activation will not be needed.

NEZ002-003-019>021-054-055-095-096-WYZ102-108-119-040845-
Dawes County-Box Butte County-Scotts Bluff County-Banner County-
Morrill County-Kimball County-Cheyenne County-
Northern Sioux County-Southern Sioux County-Niobrara County-
Goshen County-East Laramie County-
239 AM MDT Thu Aug 3 2023

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

.DAY ONE...TODAY AND TONIGHT

Scattered to numerous showers, and scattered thunderstorms will
occur this afternoon and evening, when there is a slight chance
for severe storms. Some storms this afternoon and evening may
become severe, producing quarter size hail or larger, or winds in
excess of 60 mph. A few storms north of a Torrington to Alliance
line may produce locally heavy rainfall.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

There is a chance of afternoon and evening thunderstorms Friday
through Monday, with lesser chances for Tuesday and Wednesday.

.Spotter information statement...

Spotter activation will not be needed.

Rubin

In the hours before

Special weather statement, Aug 3, 12:42 PM MDT, 2 hours 57 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
1242 PM MDT Thu Aug 3 2023

WYZ116-117-031915-
South Laramie Range WY-South Laramie Range Foothills WY-
1242 PM MDT Thu Aug 3 2023

...A strong thunderstorm will impact portions of southwestern Laramie
County through 115 PM MDT...

At 1242 PM MDT, Doppler radar was tracking a strong thunderstorm 7
miles southeast of Crystal Lake Campground, or 15 miles west of
Cheyenne, moving northeast at 5 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Crystal Lake Campground and Crystal Lake Reservoir.

This includes Interstate 80 in Wyoming between mile markers 342 and
353.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Cheyenne.

&&

LAT...LON 4101 10515 4116 10521 4121 10499 4105 10494
TIME...MOT...LOC 1842Z 244DEG 4KT 4110 10508

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

Hammer
Special weather statement, Aug 3, 1:14 PM MDT, 2 hours 25 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
114 PM MDT Thu Aug 3 2023

WYZ117-118-032000-
Central Laramie County WY-South Laramie Range Foothills WY-
114 PM MDT Thu Aug 3 2023

...A strong thunderstorm will impact portions of southwestern Laramie
County through 200 PM MDT...

At 114 PM MDT, Doppler radar was tracking a strong thunderstorm 7
miles west of Warren AFB, or 10 miles west of Cheyenne, moving
northeast at 10 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Cheyenne, South Greeley, Ranchettes, Warren AFB, Frontier Park, North
Cheyenne, Warren Af Base, Fox Farm-College and South Greeley High.

This includes the following highways...
 Interstate 25 in Wyoming between mile markers 7 and 21.
 Interstate 80 in Wyoming between mile markers 347 and 367.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Cheyenne.

&&

LAT...LON 4105 10506 4119 10514 4135 10494 4121 10471
      4111 10470
TIME...MOT...LOC 1914Z 242DEG 10KT 4115 10500

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

Hammer
Local storm report, Aug 3, 2:38 PM MDT, 1 hour 1 minute before
Preliminary Local Storm Report
National Weather Service Cheyenne WY
238 PM MDT Thu Aug 3 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0500 PM     Flood            10 SSW Muddy Gap        42.25N 107.51W
08/02/2023                   Carbon             WY   Emergency Mngr

            Late Report from Carbon County emergency
            management. Bairoil Gas Plant flooded and is
            suspending operations until the water is
            pumped out. Flooded nearby roadways reported
            as well.

&&

TT
Local storm report, Aug 3, 3:32 PM MDT, 7 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 6:23 PM MDTSpecial Weather StatementCYSAlbany67 min
Aug 2, 10:11 PM MDTSpecial Weather StatementCYSCarbon34 min
Aug 2, 11:01 PM MDTSpecial Weather StatementCYSCarbon44 min
Aug 2, 11:29 PM MDTSpecial Weather StatementCYS46 min
Aug 3, 12:17 AM MDTSpecial Weather StatementCYSAlbany43 min
Aug 3, 1:01 AM MDTSpecial Weather StatementCYSAlbany44 min
Aug 3, 12:42 PM MDTSpecial Weather StatementCYSLaramie33 min
Aug 3, 1:14 PM MDTSpecial Weather StatementCYSLaramie46 min
Aug 3, 3:00 PM MDTFlash Flood WarningCYSLaramie3 hr
Aug 3, 4:02 PM MDTSpecial Weather StatementCYSNiobrara28 min
Aug 3, 4:07 PM MDTSpecial Weather StatementCYSLaramie53 min
Aug 3, 5:09 PM MDTSpecial Weather StatementCYSNiobrara36 min
Aug 2, 6:01 PM MDTSpecial Weather StatementCYSBox Butte, Morrill44 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2023Every severe thunderstorm warning in 2023

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.