Alert archive / Wyoming / Red Flag Warnings in 2026
Red Flag Warning 21, NWS Cheyenne, WY
NWS Cheyenne, WY issued this red flag warning at May 2, 2026, 2:09 PM MDT for 4 counties in Wyoming; 4 counties in Nebraska. It was in force for 6 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
- May 2, 2026, 2:09 PM MDT (20:09 UTC)
- Expired
- May 2, 2026, 8:00 PM MDT
- In force
- 6 hr
- Issued by
- NWS Cheyenne, WY
Counties Box Butte County, NE, Dawes County, NE, Morrill County, NE, Sioux County, NE, Converse County, WY, Goshen County, WY, Niobrara County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 155 km from the middle of the area, began a volume at 20:15 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, 8.2 hours before the alert went out and 363 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
- 2845 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- -30 m²/s²
- 0-3 km storm-relative helicity
- -32 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
301 WWUS85 KCYS 022009 RFWCYS URGENT - FIRE WEATHER MESSAGE National Weather Service Cheyenne WY 209 PM MDT Sat May 2 2026 NEZ434-435-WYZ417-418-030200- /O.NEW.KCYS.FW.W.0021.260502T2009Z-260503T0200Z/ Pine Ridge/Nebraska National Forest- Box Butte/South Sioux/Niobrara River- Niobrara/Lower Elevations of Converse/Thunder Basin National Grassland- Middle North Platte River Basin/Niobrara and Converse High Plains- 209 PM MDT Sat May 2 2026 ...RED FLAG WARNING IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR LOW RH AND BREEZY WINDS UP TO 25 MPH FOR FIRE WEATHER ZONES 417, 418, 434, AND 435... The National Weather Service in Cheyenne has issued a Red Flag Warning, which is in effect until 8 PM MDT this evening. * AFFECTED AREA...Fire weather zone 434, 435, 417, 418. * WIND...West to northwest winds with gusts to 25 mph. * HUMIDITY...8 to 15 percent. * IMPACTS...any fires that develop will likely spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly. A combination of strong winds, low relative humidity, and warm temperatures can contribute to extreme fire behavior. && $$
1 follow-up statement
398 WWUS85 KCYS 030155 RFWCYS URGENT - FIRE WEATHER MESSAGE National Weather Service Cheyenne WY 755 PM MDT Sat May 2 2026 NEZ434-435-WYZ417-418-030300- /O.EXP.KCYS.FW.W.0021.000000T0000Z-260503T0200Z/ Pine Ridge/Nebraska National Forest- Box Butte/South Sioux/Niobrara River- Niobrara/Lower Elevations of Converse/Thunder Basin National Grassland- Middle North Platte River Basin/Niobrara and Converse High Plains- 755 PM MDT Sat May 2 2026 ...RED FLAG WARNING WILL EXPIRE AT 8 PM MDT THIS EVENING FOR FIRE WEATHER ZONES 417, 418, 434, AND 435... Winds will continue to taper tonight, and humidity values will recover, allowing the Red Flag Warning for east central Wyoming and the northern Nebraska panhandle to expire. $$
Nearby
Red Flag Warnings in Wyoming, 2026Red Flag Warnings in Nebraska, 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.