Alert archive / Wyoming / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 376, NWS Cheyenne, WY

August 21, 2019Albany County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 21, 2019, 5:32 PM MDT for Albany 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 counties it named.

The facts

Issued: Aug 21, 2019, 5:32 PM MDT (23:32 UTC)
Expired: Aug 21, 2019, 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

County Albany County, WY

The radar

The Cheyenne radar (KCYS), 95 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 21, 2:47 PM MDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.5 hours before the alert went out and 289 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: 406 J/kg
Mixed-layer CIN: -291 J/kg
Mixed-layer LCL: 770 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: -35 m²/s²
0-3 km storm-relative helicity: 35 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Cheyenne, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 21, 5:09 PM MDT, 23 minutes earlier.

Area forecast discussion, Aug 21, 5:09 PM MDT, 23 minutes before

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Hazardous weather outlook, Aug 21, 3:06 PM MDT, 2 hours 26 minutes before

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In the hours before

Special weather statement, Aug 21, 3:28 PM MDT, 2 hours 4 minutes before

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Special weather statement, Aug 21, 4:05 PM MDT, 1 hour 27 minutes before

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Special weather statement, Aug 21, 4:15 PM MDT, 1 hour 17 minutes before

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Special weather statement, Aug 21, 5:14 PM MDT, 18 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 6:02 PM MDT	Severe Thunderstorm Warning	CYS	Platte	7 min
Aug 20, 6:04 PM MDT	Severe Thunderstorm Warning	CYS	Platte	25 min
Aug 20, 6:12 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Platte	33 min
Aug 20, 6:20 PM MDT	Flash Flood Warning	CYS	Platte	13 hr
Aug 20, 6:27 PM MDT	Severe Thunderstorm Warning	CYS	Platte	33 min
Aug 20, 6:43 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Converse, Platte	17 min
Aug 20, 6:57 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Platte	48 min
Aug 20, 7:14 PM MDT	Special Weather Statement	CYS	Converse	61 min
Aug 20, 7:25 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Converse	18 min
Aug 20, 8:04 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Converse	26 min
Aug 20, 8:41 PM MDT	Flash Flood Warning Emergency	CYS	Platte	11 hr
Aug 20, 9:25 PM MDT	Severe Thunderstorm Warning	CYS	Goshen	50 min
Aug 20, 9:42 PM MDT	Special Weather Statement	CYS	Platte	63 min
Aug 20, 9:49 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie, Platte	41 min
Aug 20, 10:07 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie, Platte	53 min
Aug 20, 10:50 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie	55 min
Aug 20, 11:37 PM MDT	Areal Flood Advisory	CYS	Laramie	3 hr
Aug 21, 12:02 AM MDT	Special Weather Statement	CYS	Laramie	43 min
Aug 21, 3:31 AM MDT	Fire Weather Watch	CYS		10 hr
Aug 21, 7:45 AM MDT	Areal Flood Warning	CYS	Platte	3 hr
Aug 21, 7:59 AM MDT	Areal Flood Advisory	CYS	Laramie	8 hr
Aug 21, 1:54 PM MDT	Fire Weather Watch	CYS		47 hr
Aug 21, 1:54 PM MDT	Red Flag Warning	CYS		30 hr
Aug 21, 3:28 PM MDT	Special Weather Statement	CYS		32 min
Aug 21, 4:05 PM MDT	Special Weather Statement	CYS		25 min
Aug 21, 4:15 PM MDT	Special Weather Statement	CYS	Albany	30 min
Aug 21, 4:20 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Carbon, Converse	55 min
Aug 21, 4:36 PM MDT	Areal Flood Advisory	CYS	Albany, Carbon	3 hr
Aug 21, 4:49 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Carbon	26 min
Aug 21, 5:14 PM MDT	Special Weather Statement	CYS	Albany	31 min
Aug 21, 5:35 PM MDT	Areal Flood Advisory	CYS	Albany, Carbon	3 hr
Aug 20, 11:18 PM MDT	Areal Flood Advisory	CYS	Scotts Bluff	5 hr
Aug 20, 11:39 PM MDT	Severe Thunderstorm Warning	CYS	Banner, Box Butte, Cheyenne, Kimball, Morrill	66 min
Aug 21, 12:32 AM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Cheyenne, Morrill	28 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2019 Every severe thunderstorm warning in 2019

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.