Alert archive / Wyoming / Red Flag Warnings in 2026
Red Flag Warning 9, NWS Riverton, WY
NWS Riverton, WY issued this red flag warning at Apr 12, 2026, 11:30 AM MDT for Natrona County, Wyoming. It took effect at Apr 12, 2026, 12:00 PM MDT. It was in force for 8 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Apr 12, 2026, 11:30 AM MDT (17:30 UTC)
- In effect from
- Apr 12, 2026, 12:00 PM MDT
- Expired
- Apr 12, 2026, 8:00 PM MDT
- In force
- 8 hr
- Issued by
- NWS Riverton, WY
County Natrona County, WY
The radar
The Riverton/Lander radar (KRIW), 137 km from the middle of the area, began a volume at 17:27 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
Riverton, WY (KRIW), launched 12:00Z, 5.5 hours before the alert went out and 131 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2180 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- -14 m²/s²
- 0-3 km storm-relative helicity
- 9 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this red flag warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Riverton, WY wrote its last area forecast discussion before this red flag warning went out at Apr 11, 5:20 PM MDT, 18 hours 10 minutes earlier.
Area forecast discussion, Apr 11, 5:20 PM MDT, 18 hours 10 minutes before
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</html>The office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 11, 7:10 PM MDT | Special Weather Statement | RIW | Sheridan | 35 min |
| Apr 12, 3:19 PM MDT | Special Weather Statement | RIW | Fremont | 26 min |
| Apr 12, 4:40 PM MDT | Special Weather Statement | RIW | Fremont | 35 min |
Nearby
Red Flag Warnings in Wyoming, 2026Every red flag 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.