Cheyenne, Wyoming
Regional Weather Alerts
| Alert: | Air Quality Alert |
| Area(s): | Yellowstone National Park; Absaroka Mountains; Cody Foothills; North Bighorn Basin; Southwest Bighorn Basin; Southeast Bighorn Basin; Owl Creek and Bridger Mountains; Bighorn Mountains West; Bighorn Mountains Southeast; Northeast Johnson County; Southeast Johnson County; Green Mountains and Rattlesnake Range |
| Effective: | 2026-08-11 @ 12:55 pm -> 2026-08-12 @ 1:00 pm |
| Onset: | 2026-08-11 @ 12:55 pm |
| Severity: | Unknown |
| Certainty: | Unknown |
| Urgency: | Unknown |
| Issued By: | NWS Riverton WY on 2026-08-11 @ 12:55 pm |
| Headline: | Air Quality Alert issued August 11 at 11:55AM MDT by NWS Riverton WY |
| Description: |
The following message is transmitted on behalf of the Wyoming Department of Environmental Quality, Air Quality Division, and the Wyoming Department of Health. * WHAT...Air Quality Alert for Wildfire Smoke. * WHERE...Northern Wyoming and portions of central Wyoming. * WHEN...Until 12 PM Wednesday. * IMPACTS...Smoke from western United States wildfires and the Weiser Knoll fire continues to be observed across much of Wyoming. The smoke is limiting visibilities at times. HEALTH INFORMATION...The Wyoming Department of Health recommends that the elderly, young children, and individuals with respiratory problems avoid excessive physical exertion and minimize outdoor activities during this time. Wildfire smoke is made up of a variety of pollutants, including particulate matter and ozone, which can cause respiratory health effects. Although these people are most susceptible to health impacts, the Department of Health also advises that everyone should avoid prolonged exposure to poor air quality conditions. CURRENT CONDITIONS...The Wyoming Department of Environmental Quality, Air Quality Division offers near real-time air quality data for Wyoming's monitoring stations and health effects information to help the public interpret current conditions. Current air quality conditions across the state of Wyoming can be found at http://www.wyvisnet.com/. |
| Alert: | Air Quality Alert |
| Area(s): | Northeast Bighorn Mountains; Sheridan Foothills |
| Effective: | 2026-08-11 @ 12:37 pm -> 2026-08-12 @ 1:45 pm |
| Onset: | 2026-08-11 @ 12:37 pm |
| Severity: | Unknown |
| Certainty: | Unknown |
| Urgency: | Unknown |
| Issued By: | NWS Billings MT on 2026-08-11 @ 12:37 pm |
| Headline: | Air Quality Alert issued August 11 at 11:37AM MDT by NWS Billings MT |
| Description: |
The following message is transmitted on behalf of the Wyoming Department of Environmental Quality, Air Quality Division and the Wyoming Department of Health. WHAT...Air Quality Alert for Wildfire Smoke. WHERE...Sheridan County, Wyoming. WHEN...through noon Wednesday. IMPACTS...Heavy smoke from regional wildfires will continue to reduce air quality. HEALTH INFORMATION...The Wyoming Department of Health recommends the elderly, young children, and individuals with respiratory problems avoid excessive physical exertion and minimize outdoor activities during this time. Wildfire smoke is made up of a variety of pollutants, including particulate matter and ozone, which can cause respiratory health effects. Although these people are most susceptible to health impacts, the Department of Health also advises that everyone should avoid prolonged exposure to poor air quality conditions. CURRENT CONDITIONS...The Wyoming Department of Environmental Quality, Air Quality Division offers near real-time air quality data for Wyoming's monitoring stations and health effects information to help the public interpret current conditions. Current air quality conditions across the state of Wyoming can be found at http://www.wyvisnet.com/ |
| Alert: | Air Quality Alert |
| Area(s): | Northern Campbell; Southern Campbell; Western Crook; Wyoming Black Hills; Weston County Plains; Newcastle; Northeastern Crook |
| Effective: | 2026-08-11 @ 11:19 am -> 2026-08-12 @ 1:00 pm |
| Onset: | 2026-08-11 @ 11:19 am |
| Severity: | Unknown |
| Certainty: | Unknown |
| Urgency: | Unknown |
| Issued By: | NWS Rapid City SD on 2026-08-11 @ 11:19 am |
| Headline: | Air Quality Alert issued August 11 at 10:19AM MDT by NWS Rapid City SD |
| Description: |
The following message is transmitted in collaboration with the Wyoming Department of Environmental Quality, Air Quality Division, and the Wyoming Department of Health. * WHAT...Air Quality Alert for Wildfire Smoke. * WHERE...Northeast Wyoming. * WHEN...Through Noon MDT Wednesday. * IMPACTS...Poor air quality due to wildfire smoke. |
| Alert: | Red Flag Warning |
| Area(s): | Upper Green River Basin/Rock Springs BLM; Sweetwater County/Rock Springs BLM/Flaming Gorge NRA |
| Effective: | 2026-08-11 @ 3:17 am -> 2026-08-11 @ 10:00 pm |
| Onset: | 2026-08-11 @ 1:00 pm -> 2026-08-11 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-08-11 @ 3:17 am |
| Headline: | Red Flag Warning issued August 11 at 2:17AM MDT until August 11 at 9:00PM MDT by NWS Riverton WY |
| Description: |
* IMPACTS: Low Humidities...Hot Temperatures...Strong Gusty Winds...and Dry Thunderstorms with gusty and erratic outflow winds could cause erratic fire behavior. * AFFECTED AREA: In Southwest WY Fire Zone....279. In West Central WY Fire Zone....278. * COUNTIES AFFECTED: In Southwest WY...Sweetwater. In West Central WY...Lincoln...Sublette. * WIND: West 10 to 15 mph. * THUNDERSTORMS: Lightning and outflow wind gusts of 50 to 55 mph will be possible through early Tuesday evening. * HUMIDITY: As low as 14 percent. * TEMPERATURES: Highs in the middle 80s to near 90 degrees. |
| Alert: | Red Flag Warning |
| Area(s): | Natrona County/Casper BLM; Johnson County/Casper BLM; South Bighorn Mountains; Casper Mountain |
| Effective: | 2026-08-11 @ 3:17 am -> 2026-08-11 @ 10:00 pm |
| Onset: | 2026-08-11 @ 1:00 pm -> 2026-08-11 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-08-11 @ 3:17 am |
| Headline: | Red Flag Warning issued August 11 at 2:17AM MDT until August 11 at 9:00PM MDT by NWS Riverton WY |
| Description: |
* IMPACTS: Low Humidities...Hot Temperatures...and Strong Gusty Winds...could cause erratic fire behavior. * AFFECTED AREA: In Central WY Fire Zones...280...285...300. In North Central WY Fire Zone....281. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In North Central WY...Hot Springs...Johnson...Washakie. * WIND: North 10 to 20 mph with gusts up to 25 mph. * HUMIDITY: As low as 9 percent. * TEMPERATURES: Highs in the lower to middle 90s; Highs in the upper 80s in zones 285/300. |
| Alert: | Red Flag Warning |
| Area(s): | Yellowstone National Park |
| Effective: | 2026-08-11 @ 3:17 am -> 2026-08-11 @ 10:00 pm |
| Onset: | 2026-08-11 @ 1:00 pm -> 2026-08-11 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-08-11 @ 3:17 am |
| Headline: | Red Flag Warning issued August 11 at 2:17AM MDT until August 11 at 9:00PM MDT by NWS Riverton WY |
| Description: |
The National Weather Service in Riverton has issued a Red Flag Warning, which is in effect from noon today to 9 PM MDT this evening. * IMPACTS: Low Humidities...Hot Temperatures...and Strong Gusty Winds...could cause erratic fire behavior. * AFFECTED AREA: In Northwest WY...Fire Weather Zone 140. * COUNTIES AFFECTED: In Northwest WY...Yellowstone National Park. * WIND: West 10 to 15 mph with gusts up to 30 mph. * HUMIDITY: As low as 14 percent. * TEMPERATURES: Highs in the upper 70s. |
| Alert: | Red Flag Warning |
| Area(s): | Upper Wind River Basin/Wind River Basin; Owl Creek Mountains; Granite/Green/Ferris/Rattlesnake Mountains |
| Effective: | 2026-08-11 @ 3:17 am -> 2026-08-11 @ 10:00 pm |
| Onset: | 2026-08-11 @ 1:00 pm -> 2026-08-11 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-08-11 @ 3:17 am |
| Headline: | Red Flag Warning issued August 11 at 2:17AM MDT until August 11 at 9:00PM MDT by NWS Riverton WY |
| Description: |
* IMPACTS: Low Humidities...Hot Temperatures...and Strong Gusty Winds...could cause erratic fire behavior. * AFFECTED AREA: In Central WY Fire Zones...283...289. In North Central WY Fire Zone....287. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In North Central WY...Hot Springs. In Southwest WY...Sweetwater. * WIND: Northwest 10 to 15 mph with gusts up to 25 mph. * HUMIDITY: As low as 10 percent. * TEMPERATURES: Highs in the upper 80s to middle 90s. |
| Alert: | Red Flag Warning |
| Area(s): | Absaroka Mountains/North Shoshone NF |
| Effective: | 2026-08-11 @ 3:17 am -> 2026-08-11 @ 10:00 pm |
| Onset: | 2026-08-11 @ 1:00 pm -> 2026-08-11 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-08-11 @ 3:17 am |
| Headline: | Red Flag Warning issued August 11 at 2:17AM MDT until August 11 at 9:00PM MDT by NWS Riverton WY |
| Description: |
* IMPACTS: Low Humidities...Hot Temperatures...and Strong Gusty Winds...could cause erratic fire behavior. * AFFECTED AREA: In Northwest WY...Fire Weather Zone 286. * COUNTIES AFFECTED: In Central WY...Fremont. In North Central WY...Hot Springs...Park. * WIND: West 10 to 20 mph with gusts up to 30 mph. * HUMIDITY: As low as 13 percent. * TEMPERATURES: Highs in the upper 70s to middle 80s. |
| Alert: | Red Flag Warning |
| Area(s): | Niobrara/Lower Elevations of Converse/Thunder Basin National Grassland; Middle North Platte River Basin/Niobrara and Converse High Plains; North Laramie Range and Adjacent High Plains; North Laramie Valley/Shirley Basin; Ferris/Seminoe/Shirley Mountains; Central and West Carbon; Southwest Carbon County; Sierra Madre Range/Medicine Bow NF; Upper North Platte River Basin; Snowy Range/Medicine Bow NF; North Snowy Range Foothills; Southern Laramie Valley; Southern Laramie Range; Laramie Foothills and High Plains |
| Effective: | 2026-08-11 @ 2:08 am -> 2026-08-11 @ 10:00 pm |
| Onset: | 2026-08-11 @ 1:00 pm -> 2026-08-11 @ 10:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-08-11 @ 2:08 am |
| Headline: | Red Flag Warning issued August 11 at 1:08AM MDT until August 11 at 9:00PM MDT by NWS Cheyenne WY |
| Description: |
The National Weather Service in Cheyenne has issued a Red Flag Warning, which is in effect from noon to 9 PM MDT Tuesday. * AFFECTED AREA...Fire weather zones 417 through 430. * WIND...West to northwest at 15 to 20 mph with gusts up to 35 mph, turning northerly into the evening hours. * HUMIDITY...Between 8 and 16 percent. * ADDITIONAL DETAILS...Isolated high-based showers will have the potential to produce gusty and erratic winds along with a few strikes of lightning without much, if any, rainfall during the afternoon and evening hours. * IMPACTS...any fires that develop will likely spread rapidly. Outdoor burning is not recommended. |