Alert archive / Wyoming / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 215, NWS Cheyenne, WY

July 28, 2026Converse County, Niobrara County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 28, 2026, 9:07 PM MDT for Converse County, Niobrara County, Wyoming. It was in force for 23 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: Jul 28, 2026, 9:07 PM MDT (03:07 UTC)
Expired: Jul 28, 2026, 9:30 PM MDT
In force: 23 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

Counties Converse County, WY, Niobrara County, WY

The radar

The Cheyenne radar (KCYS), 208 km from the middle of the area, began a volume at 03:07 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 3.1 hours before the alert went out and 419 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: 2107 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 1599 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: -84 m²/s²
0-3 km storm-relative helicity: -15 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -1.4

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 Jul 28, 5:42 PM MDT, 3 hours 25 minutes earlier.

Area forecast discussion, Jul 28, 5:42 PM MDT, 3 hours 25 minutes before

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In the hours before

Special weather statement, Jul 28, 3:50 PM MDT, 5 hours 17 minutes before

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Local storm report, Jul 28, 4:02 PM MDT, 5 hours 5 minutes before

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Special weather statement, Jul 28, 4:09 PM MDT, 4 hours 58 minutes before

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Local storm report, Jul 28, 4:23 PM MDT, 4 hours 44 minutes before

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Special weather statement, Jul 28, 4:53 PM MDT, 4 hours 14 minutes before

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Special weather statement, Jul 28, 5:41 PM MDT, 3 hours 26 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
Jul 28, 6:56 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	34 min
Jul 28, 7:06 PM MDT	Special Weather Statement	CYS	Laramie	24 min
Jul 28, 7:07 PM MDT	Special Weather Statement	CYS	Albany	38 min
Jul 28, 7:15 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie	18 min
Jul 28, 7:51 PM MDT	Areal Flood Advisory	CYS	Laramie	3 hr
Jul 28, 8:01 PM MDT	Severe Thunderstorm Warning	CYS	Platte	29 min
Jul 28, 8:34 PM MDT	Special Weather Statement	CYS	Converse	41 min
Jul 29, 12:53 PM MDT	Special Weather Statement	CYS	Laramie	37 min
Jul 29, 3:00 PM MDT	Special Weather Statement	CYS	Platte	30 min
Jul 29, 3:49 PM MDT	Severe Thunderstorm Warning	CYS	Converse, Goshen, Niobrara, Platte	41 min
Jul 29, 4:17 PM MDT	Special Weather Statement	CYS	Laramie	28 min
Jul 29, 4:20 PM MDT	Flash Flood Warning	CYS	Laramie	3 hr
Jul 28, 6:28 PM MDT	Special Weather Statement	CYS	Cheyenne	32 min
Jul 28, 6:31 PM MDT	Special Weather Statement	CYS	Kimball	29 min
Jul 28, 7:13 PM MDT	Special Weather Statement	CYS	Sioux	32 min
Jul 28, 7:30 PM MDT	Special Weather Statement	CYS	Kimball	30 min
Jul 29, 4:40 PM MDT	Special Weather Statement	CYS	Sioux	35 min
Jul 29, 5:52 PM MDT	Special Weather Statement	CYS	Cheyenne	23 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2026 Every severe thunderstorm warning in 2026

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.