Alert archive / Wyoming / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 32, NWS Cheyenne, WY

June 6, 2021Laramie County, Platte County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 6, 2021, 5:32 PM MDT for Laramie County, Platte County, Wyoming. It was in force for 43 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: Jun 6, 2021, 5:32 PM MDT (23:32 UTC)
Expired: Jun 6, 2021, 6:15 PM MDT
In force: 43 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Laramie County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 48 km from the middle of the area, began a volume at 23:31 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

Denver, CO (KDNR), launched 12:00Z, 11.5 hours before the alert went out and 241 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2939 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 85 m²/s²
0-3 km storm-relative helicity: 76 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

689 
WUUS55 KCYS 062332
SVRCYS
WYC021-031-070015-
/O.NEW.KCYS.SV.W.0032.210606T2332Z-210607T0015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
532 PM MDT Sun Jun 6 2021

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  Northwestern Laramie County in southeastern Wyoming...
  South central Platte County in southeastern Wyoming...

* Until 615 PM MDT.

* At 531 PM MDT, a severe thunderstorm was located near Iron
  Mountain, or 28 miles northeast of Laramie, moving northeast at 20
  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 remain over mainly rural areas of
  northwestern Laramie and south central Platte Counties.

This includes Interstate 25 in Wyoming between mile markers 34 and
43.
 
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 Cheyenne.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4146 10518 4157 10522 4174 10497 4146 10476
TIME...MOT...LOC 2331Z 224DEG 17KT 4154 10512 

HAIL...1.00IN
WIND...60MPH
 
$$

Claycomb

1 follow-up statement

153 
WWUS55 KCYS 062348
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
548 PM MDT Sun Jun 6 2021

WYC021-031-070015-
/O.CON.KCYS.SV.W.0032.000000T0000Z-210607T0015Z/
Laramie WY-Platte WY-
548 PM MDT Sun Jun 6 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM MDT
FOR NORTHWESTERN LARAMIE AND SOUTH CENTRAL PLATTE COUNTIES...

At 548 PM MDT, a severe thunderstorm was located near Iron Mountain,
or 30 miles northeast of Laramie, moving northeast at 15 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 remain over mainly rural areas of
northwestern Laramie and south central Platte Counties.

This includes Interstate 25 in Wyoming between mile markers 38 and
42.
 
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
Cheyenne.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4148 10514 4157 10520 4174 10497 4154 10483
TIME...MOT...LOC 2348Z 223DEG 14KT 4157 10509 

HAIL...1.00IN
WIND...60MPH
 
$$

Claycomb

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 5, 7:16 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Niobrara, Platte	28 min
Jun 5, 7:53 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Niobrara	22 min
Jun 6, 3:24 PM MDT	Special Weather Statement	CYS	Laramie	36 min
Jun 6, 5:21 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	39 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2021 Every 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.