Alert archive / Wyoming / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 1, NWS Cheyenne, WY
NWS Cheyenne, WY issued this severe thunderstorm warning at May 16, 2021, 5:26 PM MDT for Carbon County, Wyoming. It was in force for 49 min. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- May 16, 2021, 5:26 PM MDT (23:26 UTC)
- Expired
- May 16, 2021, 6:15 PM MDT
- In force
- 49 min
- Issued by
- NWS Cheyenne, WY
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
County Carbon County, WY
The radar
The Riverton/Lander radar (KRIW), 167 km from the middle of the area, began a volume at 23:28 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 16, 5:50 PM MDT | HAIL 0.5 | Seminoe Dam, WY | THUNDERSTORM CONDITIONS LASTED AROUND 45 MINUTES, ENDING AROUND 5:45 PM. HAIL WAS MEASURED 0.5 INCH IN DIAMETER AND ACCUMULATED TO AN INCH DEEP ON THE GROUND. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Riverton, WY (KRIW), launched 12:00Z, 11.4 hours before the alert went out and 162 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
- 7 J/kg
- Mixed-layer CIN
- -44 J/kg
- Mixed-layer LCL
- 1066 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- -50 m²/s²
- 0-3 km storm-relative helicity
- 20 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
062
WUUS55 KCYS 162326
SVRCYS
WYC007-170015-
/O.NEW.KCYS.SV.W.0001.210516T2326Z-210517T0015Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
526 PM MDT Sun May 16 2021
The National Weather Service in Cheyenne has issued a
* Severe Thunderstorm Warning for...
North central Carbon County in south central Wyoming...
* Until 615 PM MDT.
* At 526 PM MDT, a severe thunderstorm was located over Seminoe Dam,
or 30 miles northeast of Rawlins, moving north at 5 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage
to roofs, siding, and trees.
* Locations impacted include...
Seminoe Campground and Seminoe Dam.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Prepare immediately for large hail and damaging winds. People outside
should move immediately to shelter inside a strong building. Stay
away from windows.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4207 10680 4207 10699 4225 10703 4225 10674
TIME...MOT...LOC 2326Z 180DEG 5KT 4215 10690
HAIL...1.00IN
WIND...60MPH
$$
Hammer2 follow-up statements
092
WWUS55 KCYS 162344
SVSCYS
Severe Weather Statement
National Weather Service Cheyenne WY
544 PM MDT Sun May 16 2021
WYC007-170015-
/O.CON.KCYS.SV.W.0001.000000T0000Z-210517T0015Z/
Carbon WY-
544 PM MDT Sun May 16 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM MDT
FOR NORTH CENTRAL CARBON COUNTY...
At 543 PM MDT, a severe thunderstorm was located over Seminoe Dam, or
30 miles northeast of Rawlins, and is nearly stationary.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
Locations impacted include...
Seminoe Campground and Seminoe Dam.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4211 10684 4211 10695 4225 10700 4225 10678
TIME...MOT...LOC 2343Z 175DEG 3KT 4216 10690
HAIL...1.00IN
WIND...60MPH
$$
Hammer287
WWUS55 KCYS 170013
SVSCYS
Severe Weather Statement
National Weather Service Cheyenne WY
613 PM MDT Sun May 16 2021
WYC007-170023-
/O.EXP.KCYS.SV.W.0001.000000T0000Z-210517T0015Z/
Carbon WY-
613 PM MDT Sun May 16 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL CARBON COUNTY
WILL EXPIRE AT 615 PM MDT...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However gusty
winds are still possible with this thunderstorm.
To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Cheyenne.
LAT...LON 4211 10684 4211 10695 4225 10700 4225 10678
TIME...MOT...LOC 0013Z 180DEG 5KT 4220 10690
$$
HammerThe office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 6:03 PM MDT | Special Weather Statement | CYS | Carbon | 57 min |
| May 15, 6:19 PM MDT | Special Weather Statement | CYS | Carbon | 56 min |
| May 16, 12:52 PM MDT | Areal Flood Advisory | CYS | Albany | 3 hr |
| May 16, 4:42 PM MDT | Special Weather Statement | CYS | 33 min | |
| May 16, 5:11 PM MDT | Special Weather Statement | CYS | Carbon | 34 min |
Nearby
Severe Thunderstorm Warnings in Wyoming, 2021Every severe thunderstorm warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.