Alert archive / Wyoming / Severe Thunderstorm Warnings in 2018
Severe Thunderstorm Warning 52, NWS Riverton, WY
NWS Riverton, WY issued this severe thunderstorm warning at Jun 29, 2018, 1:57 PM MDT for Johnson County, Wyoming. It was in force for 33 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
- Jun 29, 2018, 1:57 PM MDT (19:57 UTC)
- Expired
- Jun 29, 2018, 2:30 PM MDT
- In force
- 33 min
- Issued by
- NWS Riverton, WY
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
County Johnson County, WY
The radar
The Riverton/Lander radar (KRIW), 187 km from the middle of the area, began a volume at 20:00 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 nearest sounding before it
Riverton, WY (KRIW), launched 12:00Z, 8.0 hours before the alert went out and 182 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.
- Mixed-layer CAPE
- 256 J/kg
- Mixed-layer CIN
- -222 J/kg
- Mixed-layer LCL
- 1500 m above ground
- 0-6 km bulk shear
- 48 kt
- 0-1 km storm-relative helicity
- 59 m²/s²
- 0-3 km storm-relative helicity
- 84 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.3
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 Jun 29, 1:34 PM MDT, 23 minutes earlier.
Area forecast discussion, Jun 29, 1:34 PM MDT, 23 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, Jun 29, 2:30 AM MDT, 11 hours 27 minutes before
Hazardous Weather Outlook National Weather Service Riverton WY 230 AM MDT Fri Jun 29 2018 WYZ001>020-022>030-301100- Yellowstone National Park-Absaroka Mountains-Cody Foothills- North Big Horn Basin-Southwest Big Horn Basin- Southeast Big Horn 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- 230 AM MDT Fri Jun 29 2018 This Hazardous Weather Outlook is for Western and Central Wyoming. .DAY ONE...Today and Tonight Isolated to scattered mainly afternoon and evening thunderstorms. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Saturday...Isolated to scattered thunderstorms. Sunday through Wednesday...Elevated fire conditions in the central and south. Isolated thunderstorms Monday and Tuesday in the north and northwest. .SPOTTER INFORMATION STATEMENT... Spotters are urged to report hail and wind gusts past 45 mph. Thank you.
In the hours before
Special weather statement, Jun 29, 12:37 PM MDT, 1 hour 20 minutes before
Special Weather Statement
National Weather Service Riverton WY
1237 PM MDT FRI JUN 29 2018
WYZ004-291900-
North Big Horn Basin-
1237 PM MDT FRI JUN 29 2018
...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL BIG HORN COUNTY
UNTIL 100 PM MDT...
At 1237 PM MDT, Doppler radar was tracking a strong thunderstorm over
Manderson, or 10 miles south of Basin, moving northeast at 35 mph.
Nickel size hail, wind gusts of 40 to 50 mph, and brief heavy rain
will be possible with this storm.
This storm will remain over mainly rural areas of south central Big
Horn County.
LAT...LON 4436 10766 4418 10761 4417 10794 4417 10805
4431 10809 4448 10785
TIME...MOT...LOC 1837Z 246DEG 30KT 4424 10797
CNJSpecial weather statement, Jun 29, 12:46 PM MDT, 1 hour 11 minutes before
Special Weather Statement
National Weather Service Riverton WY
1246 PM MDT FRI JUN 29 2018
WYZ006-008-291915-
Southeast Big Horn Basin-Bighorn Mountains West-
1246 PM MDT FRI JUN 29 2018
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN WASHAKIE COUNTY
UNTIL 115 PM MDT...
At 1245 PM MDT, Doppler radar was tracking a strong thunderstorm near
Ten Sleep, moving northeast at 25 mph.
Half inch hail and winds in excess of 40 mph will be possible with
this storm.
This strong thunderstorm will be near...
Ten Sleep around 105 PM MDT.
Tensleep Canyon around 115 PM MDT.
Other locations impacted by this storm include Leigh Creek Campground
and Wigwam Fish Rearing Station.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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 4427 10748 4410 10718 4386 10752 4396 10772
4417 10756 4417 10746 4420 10747 4423 10747
4424 10748 4426 10749
TIME...MOT...LOC 1845Z 216DEG 21KT 4397 10756
TLSpecial weather statement, Jun 29, 12:55 PM MDT, 1 hour 2 minutes before
Special Weather Statement National Weather Service Riverton WY 1255 PM MDT FRI JUN 29 2018 WYZ009>011-291930- Southeast Johnson County-Northeast Johnson County-Bighorn Mountains Southeast- 1255 PM MDT FRI JUN 29 2018 ...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL JOHNSON COUNTY UNTIL 130 PM MDT... At 1254 PM MDT, Doppler radar was tracking a strong thunderstorm 11 miles north of Mayoworth, or 19 miles north of Kaycee, moving northeast at 30 mph. One-half inch diameter hail, brief heavy rain and wind gusts around 45 mph will be possible with this storm. This storm will remain over mainly rural areas of central Johnson County, but will cross Interstate 25 between mile markers 268 and 288. LAT...LON 4385 10673 4396 10689 4425 10662 4410 10624 TIME...MOT...LOC 1854Z 221DEG 26KT 4399 10671 CNJ
Special weather statement, Jun 29, 12:59 PM MDT, 58 minutes before
Special Weather Statement
National Weather Service Riverton WY
1259 PM MDT FRI JUN 29 2018
WYZ004-008-009-291945-
North Big Horn Basin-Bighorn Mountains Southeast-Bighorn Mountains
West-
1259 PM MDT FRI JUN 29 2018
...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN BIG HORN COUNTY
UNTIL 145 PM MDT...
At 1257 PM MDT, Doppler radar was tracking a strong thunderstorm 7
miles northwest of Hyattville, or 17 miles east of Basin, moving
northeast at 40 mph.
Pea to penny sized hail, wind gusts of 40 to 50 mph, and brief heavy
rain will be possible with this storm.
This strong thunderstorm will be near...
Medicine Lodge Archaeological Site around 105 to 110 PM MDT.
Other locations impacted by this storm include Paint Rock Lodge.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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 4459 10739 4456 10737 4456 10734 4435 10714
4421 10777 4437 10787 4460 10741
TIME...MOT...LOC 1857Z 240DEG 40KT 4434 10770
CNJSpecial weather statement, Jun 29, 1:09 PM MDT, 48 minutes before
Special Weather Statement
National Weather Service Riverton WY
109 PM MDT FRI JUN 29 2018
WYZ005-006-291945-
Southeast Big Horn Basin-Southwest Big Horn Basin-
109 PM MDT FRI JUN 29 2018
...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL HOT SPRINGS AND
NORTHWESTERN WASHAKIE COUNTIES UNTIL 145 PM MDT...
At 108 PM MDT, Doppler radar was tracking a strong thunderstorm over
Winchester, or 12 miles southwest of Worland, moving northeast at 40
mph.
Half inch hail and winds in excess of 40 mph will be possible with
this storm.
This strong thunderstorm will be near...
Wyoming Boys School around 120 PM MDT.
Worland and Worland Municipal Airport around 125 PM MDT.
Other locations impacted by this storm include Washakie County
Fairgrounds.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
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 4401 10756 4372 10816 4388 10834 4417 10787
4417 10773
TIME...MOT...LOC 1908Z 232DEG 36KT 4388 10811
TLSpecial weather statement, Jun 29, 1:12 PM MDT, 45 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>The office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 28, 8:29 PM MDT | Special Weather Statement | RIW | Big Horn | 46 min |
| Jun 29, 10:39 AM MDT | Special Weather Statement | RIW | Big Horn | 36 min |
| Jun 29, 11:10 AM MDT | Special Weather Statement | RIW | Hot Springs | 35 min |
| Jun 29, 11:14 AM MDT | Tornado Warning | RIW | Big Horn, Washakie | 16 min |
| Jun 29, 11:28 AM MDT | Tornado Warning | RIW | Big Horn, Washakie | 32 min |
| Jun 29, 11:33 AM MDT | Special Weather Statement | RIW | Big Horn | 42 min |
| Jun 29, 11:46 AM MDT | Special Weather Statement | RIW | Big Horn | 44 min |
| Jun 29, 11:50 AM MDT | Tornado Warning | RIW | Washakie | 25 min |
| Jun 29, 11:58 AM MDT | Tornado Warning | RIW | Big Horn | 32 min |
| Jun 29, 12:15 PM MDT | Tornado Warning | RIW | Big Horn, Washakie | 30 min |
| Jun 29, 12:25 PM MDT | Special Weather Statement | RIW | Johnson | 35 min |
| Jun 29, 12:37 PM MDT | Special Weather Statement | RIW | Big Horn | 23 min |
| Jun 29, 12:46 PM MDT | Special Weather Statement | RIW | Washakie | 29 min |
| Jun 29, 12:55 PM MDT | Special Weather Statement | RIW | Johnson | 35 min |
| Jun 29, 12:59 PM MDT | Special Weather Statement | RIW | Big Horn | 46 min |
| Jun 29, 1:09 PM MDT | Special Weather Statement | RIW | Washakie | 36 min |
| Jun 29, 1:12 PM MDT | Special Weather Statement | RIW | 33 min | |
| Jun 29, 1:17 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn, Johnson | 43 min |
| Jun 29, 1:25 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 35 min |
Nearby
Severe Thunderstorm Warnings in Wyoming, 2018Every severe thunderstorm warning in 2018
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.