Alert archive / Colorado / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 258, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 22, 2026, 12:02 AM MDT for Larimer County, Weld County, Colorado. It was in force for 17 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 22, 2026, 12:02 AM MDT (06:02 UTC)
- Expired
- Jul 22, 2026, 12:19 AM MDT
- In force
- 17 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Larimer County, CO, Weld County, CO
The radar
The Cheyenne radar (KCYS), 61 km from the middle of the area, began a volume at 06:03 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
Grand Junction, CO (KGJT), launched 00:00Z, 6.0 hours before the alert went out and 347 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.
- Mixed-layer CAPE
- 771 J/kg
- Mixed-layer CIN
- -5 J/kg
- Mixed-layer LCL
- 3633 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.9
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 Jul 21, 11:21 PM MDT, 41 minutes earlier.
Area forecast discussion, Jul 21, 11:21 PM MDT, 41 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 |
|---|---|---|---|---|
| Jul 21, 6:01 PM MDT | Areal Flood Advisory | BOU | Park | 3 hr |
| Jul 21, 6:22 PM MDT | Severe Thunderstorm Warning | BOU | Grand, Jackson, Larimer | 23 min |
| Jul 21, 7:21 PM MDT | Areal Flood Advisory | BOU | Larimer | 114 min |
| Jul 21, 8:29 PM MDT | Areal Flood Advisory | BOU | Larimer | 2 hr |
| Jul 21, 9:12 PM MDT | Areal Flood Advisory | BOU | Larimer | 3 hr |
| Jul 21, 11:53 PM MDT | Areal Flood Advisory | BOU | Larimer | 3 hr |
| Jul 22, 1:24 PM MDT | Areal Flood Advisory | BOU | Larimer | 3 hr |
| Jul 22, 2:09 PM MDT | Areal Flood Advisory | BOU | Larimer | 3 hr |
| Jul 22, 2:36 PM MDT | Areal Flood Advisory | BOU | Jefferson, Park | 34 min |
| Jul 22, 3:10 PM MDT | Flash Flood Warning | BOU | Jefferson, Park | 3 hr |
| Jul 22, 3:19 PM MDT | Areal Flood Advisory | BOU | Larimer | 3 hr |
| Jul 22, 4:13 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe, Denver, Weld | 32 min |
| Jul 22, 5:39 PM MDT | Areal Flood Advisory | BOU | Lincoln | 4 hr |
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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.