Alert archive / Wyoming / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 21, NWS Riverton, WY
NWS Riverton, WY issued this severe thunderstorm warning at Sep 12, 2021, 6:21 PM MDT for Lincoln County, Wyoming. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Sep 12, 2021, 6:21 PM MDT (00:21 UTC)
- Expired
- Sep 12, 2021, 6:45 PM MDT
- In force
- 24 min
- Issued by
- NWS Riverton, WY
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
County Lincoln County, WY
The radar
The Pocatello radar (KSFX), 155 km from the middle of the area, began a volume at 00:23 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
Salt Lake City I, UT (KSLC), launched 00:00Z, 0.4 hours before the alert went out and 208 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
- 642 J/kg
- Mixed-layer CIN
- -52 J/kg
- Mixed-layer LCL
- 2449 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 36 m²/s²
- 0-3 km storm-relative helicity
- 123 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.0
The text
As transmitted.
711
WUUS55 KRIW 130021
SVRRIW
WYC023-130045-
/O.NEW.KRIW.SV.W.0021.210913T0021Z-210913T0045Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Riverton WY
621 PM MDT Sun Sep 12 2021
The National Weather Service in Riverton has issued a
* Severe Thunderstorm Warning for...
West central Lincoln County in west central Wyoming...
* Until 645 PM MDT.
* At 620 PM MDT, a severe thunderstorm was located 10 miles east of
Georgetown, or 15 miles northeast of Montpelier, moving east at 30
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.
* This severe thunderstorm will be near...
Smoot and Salt River Pass around 645 PM MDT.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Riverton.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4244 11104 4263 11105 4263 11104 4265 11075
4238 11077 4241 11105
TIME...MOT...LOC 0020Z 271DEG 25KT 4253 11117
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
TL1 follow-up statement
793
WWUS55 KRIW 130042
SVSRIW
Severe Weather Statement
National Weather Service Riverton WY
642 PM MDT Sun Sep 12 2021
WYC023-130052-
/O.EXP.KRIW.SV.W.0021.000000T0000Z-210913T0045Z/
Lincoln-
642 PM MDT Sun Sep 12 2021
...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL LINCOLN COUNTY
WILL EXPIRE AT 645 PM MDT...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However small hail
and gusty winds are still possible with this thunderstorm.
To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Riverton.
LAT...LON 4244 11104 4263 11105 4263 11104 4265 11075
4238 11077 4241 11105
TIME...MOT...LOC 0042Z 271DEG 25KT 4253 11102
$$
TLThe office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 12, 6:25 PM MDT | Special Weather Statement | RIW | Sublette | 35 min |
| Sep 12, 6:44 PM MDT | Special Weather Statement | RIW | Lincoln | 31 min |
| Sep 12, 7:59 PM MDT | Special Weather Statement | RIW | 31 min | |
| Sep 12, 8:25 PM MDT | Special Weather Statement | RIW | 35 min | |
| Sep 12, 8:30 PM MDT | Special Weather Statement | RIW | 30 min | |
| Sep 12, 8:50 PM MDT | Special Weather Statement | RIW | 25 min | |
| Sep 12, 10:10 PM MDT | Special Weather Statement | RIW | Natrona | 35 min |
| Sep 12, 10:20 PM MDT | Special Weather Statement | RIW | 25 min | |
| Sep 12, 10:53 PM MDT | Special Weather Statement | RIW | Lincoln | 37 min |
| Sep 12, 11:46 PM MDT | Special Weather Statement | RIW | 29 min | |
| Sep 12, 11:49 PM MDT | Special Weather Statement | RIW | 26 min | |
| Sep 12, 11:52 PM MDT | Special Weather Statement | RIW | 23 min | |
| Sep 13, 1:56 AM MDT | Special Weather Statement | RIW | Sweetwater | 34 min |
| Sep 13, 2:35 AM MDT | Special Weather Statement | RIW | 40 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.