Alert archive / Colorado / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 17, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 21, 2026, 4:30 PM MDT for Logan County, Colorado. It was in force for 30 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
- May 21, 2026, 4:30 PM MDT (22:30 UTC)
- Expired
- May 21, 2026, 5:00 PM MDT
- In force
- 30 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Tornado
- Possible
- Hail
- 1.0 in
- Wind
- 60.0 mph
County Logan County, CO
The radar
The Cheyenne radar (KCYS), 150 km from the middle of the area, began a volume at 22:30 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 |
|---|---|---|---|
| May 21, 2:55 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
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 Denver/Boulder, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at May 20, 5:44 PM MDT, 22 hours 46 minutes earlier.
Area forecast discussion, May 20, 5:44 PM MDT, 22 hours 46 minutes before
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</html>The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 2:53 PM MDT | Special Weather Statement | BOU | Arapahoe | 37 min |
| May 21, 3:30 PM MDT | Severe Thunderstorm Warning | BOU | Arapahoe | 30 min |
| May 21, 3:57 PM MDT | Severe Thunderstorm Warning | BOU | Logan | 33 min |
| May 21, 4:33 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe, Washington | 42 min |
| May 21, 4:52 PM MDT | Tornado Warning | BOU | Lincoln, Washington | 38 min |
| May 21, 5:22 PM MDT | Tornado Warning | BOU | Lincoln, Washington | 38 min |
| May 21, 5:32 PM MDT | Severe Thunderstorm Warning | BOU | Logan | 43 min |
| May 21, 5:56 PM MDT | Tornado Warning | BOU | Washington | 36 min |
| May 21, 5:59 PM MDT | Tornado Warning | BOU | Washington | 31 min |
Nearby
Severe Thunderstorm Warnings in Colorado, 2026Every 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; radar from the NEXRAD Level II archive.