Alert archive / Wyoming / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 38, NWS Cheyenne, WY

June 8, 2021Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 8, 2021, 6:45 PM MDT for Laramie County, Wyoming. It was in force for 45 min. 10 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
Jun 8, 2021, 6:45 PM MDT (00:45 UTC)
Expired
Jun 8, 2021, 7:30 PM MDT
In force
45 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Hail
1.25 in
Wind
60.0 mph

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 6 km from the middle of the area, began a volume at 00:44 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

TimeReportWhereRemark
Jun 8, 6:49 PM MDTHAIL 12 Se Warren Af Base, WY
Jun 8, 7:15 PM MDTHAIL 0.252 E Cheyenne, WY
Jun 8, 7:15 PM MDTHAIL 1.52 Wnw Cheyenne, WYREPORT RECEIVED VIA FACEBOOK. DELAYED REPORT. I25 AND VANDEHEI.
Jun 8, 7:19 PM MDTHAIL 0.53 E Cheyenne, WY
Jun 8, 7:25 PM MDTHAIL 0.72 E Cheyenne, WY
Jun 8, 7:35 PM MDTHAIL 0.71 Ne Cheyenne, WY
Jun 8, 7:36 PM MDTTSTM WND GST 678 Wsw Hillsdale, WYCORRECTS PREVIOUS NON-TSTM WND GST REPORT FROM 8 WSW HILLSDALE. MESONET STATION WY46 9.7 E CHEYENNE (WYDOT).
Jun 8, 7:36 PM MDTNON-TSTM WND GST 678 Wsw Hillsdale, WYMESONET STATION WY46 9.7 E CHEYENNE (WYDOT).
Jun 8, 7:40 PM MDTHAIL 13 Ne Cheyenne, WYREPORT RECEIVED VIA FACEBOOK. DELAYED REPORT.
Jun 8, 7:40 PM MDTHAIL 15 Ene 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, 0.8 hours before the alert went out and 201 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-pSkew-T log-p diagram, Denver, CO at 00:00Z on 2021-06-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 424 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2021-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 92 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
424 J/kg
Mixed-layer CIN
-54 J/kg
Mixed-layer LCL
3769 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
92 m²/s²
0-3 km storm-relative helicity
155 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

As transmitted.

917 
WUUS55 KCYS 090045
SVRCYS
WYC021-090130-
/O.NEW.KCYS.SV.W.0038.210609T0045Z-210609T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
645 PM MDT Tue Jun 8 2021

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  Southwestern Laramie County in southeastern Wyoming...

* Until 730 PM MDT.

* At 645 PM MDT, a severe thunderstorm was located over Warren AFB,
  or near Cheyenne, moving northeast at 5 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, Ranchettes, Warren AFB, Frontier Park, North Cheyenne,
  Warren Af Base, South Greeley, Fox Farm-College and South Greeley
  High.

This includes the following highways...
 Interstate 25 in Wyoming between mile markers 8 and 23.
 Interstate 80 in Wyoming between mile markers 352 and 373.

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.

&&

LAT...LON 4107 10499 4118 10504 4142 10475 4113 10459
TIME...MOT...LOC 0045Z 241DEG 6KT 4116 10491 

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

Hammer
1 follow-up statement
780 
WWUS55 KCYS 090107
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
707 PM MDT Tue Jun 8 2021

WYC021-090130-
/O.CON.KCYS.SV.W.0038.000000T0000Z-210609T0130Z/
Laramie WY-
707 PM MDT Tue Jun 8 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM MDT
FOR SOUTHWESTERN LARAMIE COUNTY...

At 707 PM MDT, a severe thunderstorm was located over Warren Af Base,
or near Cheyenne, moving northeast at 5 mph.

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

SOURCE...Trained weather spotters.

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

Locations impacted include...
Cheyenne, Ranchettes, Warren AFB, Frontier Park, North Cheyenne,
Warren Af Base, South Greeley, Fox Farm-College and South Greeley
High.

This includes the following highways...
 Interstate 25 in Wyoming between mile markers 8 and 23.
 Interstate 80 in Wyoming between mile markers 352 and 373.

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.

&&

LAT...LON 4107 10499 4118 10504 4142 10475 4113 10459
TIME...MOT...LOC 0107Z 241DEG 6KT 4118 10487 

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

Hammer

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 8, 6:14 PM MDTSpecial Weather StatementCYSLaramie31 min
Jun 8, 7:27 PM MDTSevere Thunderstorm WarningCYSLaramie48 min
Jun 8, 7:30 PM MDTFlash Flood WarningCYSLaramie3 hr
Jun 8, 8:21 PM MDTSpecial Weather StatementCYSNiobrara54 min
Jun 8, 8:29 PM MDTSpecial Weather StatementCYSLaramie46 min
Jun 8, 8:35 PM MDTSevere Thunderstorm WarningCYSNiobrara55 min
Jun 8, 8:36 PM MDTSpecial Weather StatementCYSLaramie39 min
Jun 8, 9:03 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie42 min
Jun 8, 9:08 PM MDTSevere Thunderstorm WarningCYSLaramie52 min
Jun 8, 9:33 PM MDTSpecial Weather StatementCYSNiobrara57 min
Jun 8, 10:20 PM MDTAreal Flood AdvisoryCYSLaramie3 hr
Jun 8, 10:26 PM MDTSevere Thunderstorm WarningCYSLaramie49 min
Jun 8, 11:15 PM MDTSevere Thunderstorm WarningCYSLaramie45 min
Jun 9, 2:11 PM MDTHigh Wind WatchCYSAlbany, Converse, Goshen, Laramie, Niobrara, Platte12 hr
Jun 9, 2:11 PM MDTHigh Wind WarningCYSAlbany, Carbon, Converse, Goshen, Laramie, Niobrara and 1 more39 hr

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.