Alert archive / Wyoming / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 110, NWS Cheyenne, WY

July 29, 2021Albany County, Carbon County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 29, 2021, 2:27 PM MDT for Albany County, Carbon County, Wyoming. It was in force for 48 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: Jul 29, 2021, 2:27 PM MDT (20:27 UTC)
Expired: Jul 29, 2021, 3:15 PM MDT
In force: 48 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

Counties Albany County, WY, Carbon County, WY

The radar

The Cheyenne radar (KCYS), 120 km from the middle of the area, began a volume at 20:26 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, 8.5 hours before the alert went out and 258 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: 1746 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: 90 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

850 
WUUS55 KCYS 292027
SVRCYS
WYC001-007-292115-
/O.NEW.KCYS.SV.W.0110.210729T2027Z-210729T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
227 PM MDT Thu Jul 29 2021

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  East central Carbon County in south central Wyoming...
  West central Albany County in southeastern Wyoming...

* Until 315 PM MDT.

* At 227 PM MDT, a severe thunderstorm was located over Brooklyn Lake
  Campground, or 36 miles west of Laramie, moving northeast at 20
  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...
  Nash Fork Campground, Brooklyn Lake, Sugar Loaf Campground,
  Brooklyn Lake Campground, Deep Creek Campground, North Fork
  Campground and Arlington.

This includes Interstate 80 in Wyoming between mile markers 270 and
296.
 
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 4131 10628 4140 10638 4169 10621 4141 10580
TIME...MOT...LOC 2027Z 223DEG 18KT 4138 10627 

HAIL...1.25IN
WIND...60MPH
 
$$

Claycomb

1 follow-up statement

696 
WWUS55 KCYS 292047
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
247 PM MDT Thu Jul 29 2021

WYC001-007-292115-
/O.CON.KCYS.SV.W.0110.000000T0000Z-210729T2115Z/
Carbon WY-Albany WY-
247 PM MDT Thu Jul 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM MDT
FOR EAST CENTRAL CARBON AND WEST CENTRAL ALBANY COUNTIES...

At 247 PM MDT, a severe thunderstorm was located near Deep Creek
Campground, or 33 miles west of Laramie, moving northeast at 20 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...
Nash Fork Campground, Brooklyn Lake, Sugar Loaf Campground, Brooklyn
Lake Campground, Deep Creek Campground, North Fork Campground and
Arlington.

This includes Interstate 80 in Wyoming between mile markers 270 and
293.
 
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 4131 10628 4141 10635 4169 10621 4144 10587
TIME...MOT...LOC 2047Z 220DEG 17KT 4145 10620 

HAIL...1.25IN
WIND...60MPH
 
$$

Claycomb

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 29, 2:01 PM MDT	Flash Flood Watch	CYS	Albany, Carbon, Converse, Goshen, Laramie, Platte	34 hr
Jul 29, 2:23 PM MDT	Flash Flood Warning	CYS	Albany, Carbon	101 min
Jul 29, 3:12 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Carbon	48 min
Jul 29, 3:19 PM MDT	Flash Flood Warning	CYS	Albany, Carbon	104 min
Jul 29, 3:52 PM MDT	Severe Thunderstorm Warning	CYS	Albany	38 min
Jul 29, 4:41 PM MDT	Areal Flood Advisory	CYS	Albany	3 hr

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.