Alert archive / Wyoming / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 127, NWS Cheyenne, WY

August 14, 2021Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 14, 2021, 7:01 PM MDT for Laramie County, Wyoming. It was in force for 44 min. 5 reports 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: Aug 14, 2021, 7:01 PM MDT (01:01 UTC)
Expired: Aug 14, 2021, 7:45 PM MDT
In force: 44 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 14 km from the middle of the area, began a volume at 01:05 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
Aug 14, 7:05 PM MDT	HAIL 1	5 Ne Cheyenne, WY
Aug 14, 7:10 PM MDT	HAIL 1.75	8 Ne Cheyenne, WY
Aug 14, 7:25 PM MDT	HAIL 1	3 E Cheyenne, WY	WIND GUSTS UP TO 50 MPH WAS ALSO REPORTED WITH THIS STORM.
Aug 14, 7:25 PM MDT	HAIL 1	4 E Cheyenne, WY
Aug 14, 7:52 PM MDT	HAIL 1	9 Se Cheyenne, WY

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 1.0 hours before the alert went out and 191 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: 666 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 3335 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: -22 m²/s²
0-3 km storm-relative helicity: 81 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.4

Open this sounding in Storm Lab

The text

As transmitted.

545 
WUUS55 KCYS 150101
SVRCYS
WYC021-150145-
/O.NEW.KCYS.SV.W.0127.210815T0101Z-210815T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
701 PM MDT Sat Aug 14 2021

The National Weather Service in Cheyenne has issued a

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

* Until 745 PM MDT.

* At 701 PM MDT, a severe thunderstorm was located near Ranchettes,
  or 10 miles northeast of Cheyenne, moving south 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.

* Locations impacted include...
  Cheyenne and Ranchettes. 

This includes Interstate 80 in Wyoming between mile markers 366 and
378.
 
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.

&&

LAT...LON 4131 10474 4132 10459 4103 10444 4104 10473
TIME...MOT...LOC 0101Z 348DEG 12KT 4125 10465 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Claycomb

1 follow-up statement

941 
WWUS55 KCYS 150130
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
730 PM MDT Sat Aug 14 2021

WYC021-150145-
/O.CON.KCYS.SV.W.0127.000000T0000Z-210815T0145Z/
Laramie WY-
730 PM MDT Sat Aug 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM MDT
FOR SOUTH CENTRAL LARAMIE COUNTY...

At 730 PM MDT, a severe thunderstorm was located 7 miles east of
Cheyenne, moving south at 15 mph.

HAZARD...60 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Cheyenne and Ranchettes. 

This includes Interstate 80 in Wyoming between mile markers 366 and
378.
 
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.

&&

LAT...LON 4121 10473 4127 10457 4103 10444 4104 10473
TIME...MOT...LOC 0130Z 353DEG 12KT 4115 10465 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Claycomb

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 14, 7:12 PM MDT	Severe Thunderstorm Warning Considerable damage threat	CYS	Laramie	48 min
Aug 14, 7:36 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	39 min
Aug 15, 12:42 PM MDT	Areal Flood Advisory	CYS	Albany, Carbon	3 hr
Aug 15, 1:03 PM MDT	Special Weather Statement	CYS	Platte	42 min
Aug 15, 1:06 PM MDT	Areal Flood Advisory	CYS	Albany	3 hr
Aug 15, 1:42 PM MDT	Areal Flood Advisory	CYS	Albany, Carbon, Converse	2 hr
Aug 15, 2:10 PM MDT	Special Weather Statement	CYS	Albany	35 min
Aug 15, 2:21 PM MDT	Special Weather Statement	CYS	Albany	24 min
Aug 15, 3:47 PM MDT	Special Weather Statement	CYS	Albany	28 min
Aug 15, 3:49 PM MDT	Special Weather Statement	CYS	Albany	26 min
Aug 15, 4:25 PM MDT	Special Weather Statement	CYS	Albany	50 min
Aug 15, 4:46 PM MDT	Flash Flood Warning Considerable damage threat	CYS	Albany	95 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.