Alert archive / Wyoming / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 9, NWS Riverton, WY

July 1, 2024Hot Springs County, Washakie County, Wyoming

NWS Riverton, WY issued this severe thunderstorm warning at Jul 1, 2024, 3:41 PM MDT for Hot Springs County, Washakie County, Wyoming. It was in force for 49 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
Jul 1, 2024, 3:41 PM MDT (21:41 UTC)
Expired
Jul 1, 2024, 4:30 PM MDT
In force
49 min
Issued by
NWS Riverton, WY
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties Hot Springs County, WY, Washakie County, WY

The radar

The Riverton/Lander radar (KRIW), 89 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 nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 9.7 hours before the alert went out and 87 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, Riverton, WY at 12:00Z on 2024-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 318 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, Riverton, WY at 12:00Z on 2024-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 141 square meters per square second.1939587897117Sfc1 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
318 J/kg
Mixed-layer CIN
-275 J/kg
Mixed-layer LCL
1572 m above ground
0-6 km bulk shear
67 kt
0-1 km storm-relative helicity
141 m²/s²
0-3 km storm-relative helicity
306 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

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 Riverton, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 1, 1:52 PM MDT, 1 hour 49 minutes earlier.

Area forecast discussion, Jul 1, 1:52 PM MDT, 1 hour 49 minutes before
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Hazardous weather outlook, Jul 1, 1:46 PM MDT, 1 hour 55 minutes before
Hazardous Weather Outlook
National Weather Service Riverton WY
146 PM MDT Mon Jul 1 2024

WYZ001>020-022>030-030000-
Yellowstone National Park-Absaroka Mountains-Cody Foothills-
North Bighorn Basin-Southwest Bighorn Basin-Southeast Bighorn Basin-
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-Northeast Johnson County-
Southeast Johnson County-Teton and Gros Ventre Mountains-
Jackson Hole-Wind River Mountains West-Wind River Mountains East-
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Green Mountains and Rattlesnake Range-
Natrona County Lower Elevations-Casper Mountain-Star Valley-
Salt River and Wyoming Ranges-Upper Green River Basin Foothills-
Upper Green River Basin-South Lincoln County-
Rock Springs and Green River-Flaming Gorge-East Sweetwater County-
146 PM MDT Mon Jul 1 2024

This Hazardous Weather Outlook is for Western and Central Wyoming.

.DAY ONE...This afternoon and tonight.

Strong to severe storms are possible, mainly for the Bighorn Basin
and Johnson County. Strong sudden wind gusts, large hail, and
frequent lightning are the main threats with these storms.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday through Thursday...Shower and thunderstorm chances, mainly
for northern Wyoming, continue through midweek. Warm, dry, and breezy
conditions across south-central and southwest Wyoming through the
week will create critical fire weather conditions where the fuels
are cured.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures.

In the hours before

Special weather statement, Jul 1, 2:11 PM MDT, 1 hour 30 minutes before
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Special weather statement, Jul 1, 2:37 PM MDT, 1 hour 4 minutes before
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Special weather statement, Jul 1, 2:43 PM MDT, 58 minutes before
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Local storm report, Jul 1, 2:47 PM MDT, 54 minutes before
Preliminary Local Storm Report
National Weather Service Riverton WY
247 PM MDT Mon Jul 1 2024

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

0238 PM     Tstm Wnd Gst     2 NW Greybull           44.52N 108.08W
07/01/2024  M59 MPH          Big Horn           WY   ASOS

            ASOS station KGEY Greybull Airport.

&&

CFH
Special weather statement, Jul 1, 3:00 PM MDT, 41 minutes before
Special Weather Statement
National Weather Service Riverton WY
300 PM MDT Mon Jul 1 2024

WYZ004-008-009-012130-
Bighorn Mountains Southeast-North Bighorn Basin-Bighorn Mountains
West-
300 PM MDT Mon Jul 1 2024

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN JOHNSON...
SOUTHEASTERN BIG HORN AND NORTHEASTERN WASHAKIE COUNTIES THROUGH 330
PM MDT...

At 300 PM MDT, Doppler radar was tracking a strong thunderstorm near
Shell Canyon, which is 19 miles east of Greybull, moving east at 45
mph.

HAZARD...Wind gusts of 50 to 55 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.

This strong thunderstorm will be near...
  Upper Medicine Lodge Lake around 320 PM MDT.

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 4466 10752 4465 10754 4463 10752 4464 10750
      4461 10747 4461 10743 4460 10742 4460 10739
      4456 10737 4456 10696 4406 10712 4414 10743
      4417 10746 4417 10754 4425 10788 4470 10762
TIME...MOT...LOC 2100Z 283DEG 39KT 4451 10767

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...55 MPH

Hensley
Special weather statement, Jul 1, 3:34 PM MDT, 7 minutes before
Special Weather Statement
National Weather Service Riverton WY
334 PM MDT Mon Jul 1 2024

WYZ008>010-012200-
Bighorn Mountains Southeast-Northeast Johnson County-Bighorn
Mountains West-
334 PM MDT Mon Jul 1 2024

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN JOHNSON...
SOUTHEASTERN BIG HORN AND NORTHEASTERN WASHAKIE COUNTIES THROUGH 400
PM MDT...

At 334 PM MDT, Doppler radar was tracking a strong thunderstorm near
Cloud Peak, which is 19 miles west of Buffalo, moving east at 40 mph.

HAZARD...Wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

This storm will remain over mainly rural areas of northwestern
Johnson, southeastern Big Horn and northeastern Washakie Counties,
including the following locations... South Fork Campground, Buffalo
Johnson County Airport, and Lost Cabin Campground.

This includes Interstate 90 between mile markers 42 and 56.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4437 10670 4416 10678 4416 10682 4410 10681
      4406 10682 4415 10744 4417 10746 4419 10747
      4440 10730 4456 10731 4456 10667
TIME...MOT...LOC 2134Z 268DEG 35KT 4436 10711

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

Rowe

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 1, 7:35 AM MDTSpecial Weather StatementRIWBig Horn25 min
Jul 1, 9:40 AM MDTSpecial Weather StatementRIWBig Horn20 min
Jul 1, 2:11 PM MDTSpecial Weather StatementRIWHot Springs34 min
Jul 1, 2:17 PM MDTSevere Thunderstorm WarningRIWHot Springs, Park, Washakie43 min
Jul 1, 2:37 PM MDTSpecial Weather StatementRIWBig Horn23 min
Jul 1, 2:43 PM MDTSpecial Weather StatementRIWHot Springs32 min
Jul 1, 3:00 PM MDTSpecial Weather StatementRIWBig Horn30 min
Jul 1, 3:00 PM MDTSevere Thunderstorm WarningRIWHot Springs, Washakie45 min
Jul 1, 3:34 PM MDTSpecial Weather StatementRIWJohnson26 min
Jul 1, 3:59 PM MDTSpecial Weather StatementRIWSheridan46 min
Jul 1, 4:25 PM MDTSevere Thunderstorm WarningRIWJohnson, Washakie35 min
Jul 1, 5:04 PM MDTSpecial Weather StatementRIWJohnson26 min
Jul 1, 5:26 PM MDTSevere Thunderstorm WarningRIWNatrona49 min
Jul 1, 5:35 PM MDTSpecial Weather StatementRIWJohnson25 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2024Every severe thunderstorm warning in 2024

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.