Cheyenne, Wyoming
Regional Weather Alerts
| Alert: | Flood Watch |
| Area(s): | Yellowstone National Park; Absaroka Mountains; Cody Foothills; Owl Creek and Bridger Mountains; Bighorn Mountains West; Bighorn Mountains Southeast; Northeast Johnson County; Southeast Johnson County |
| Effective: | 2026-09-19 @ 2:34 am -> 2026-09-19 @ 7:00 pm |
| Onset: | 2026-09-19 @ 2:34 am -> 2026-09-20 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Riverton WY on 2026-09-19 @ 2:34 am |
| Headline: | Flood Watch issued September 19 at 1:34AM MDT until September 20 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Flash flooding caused by moderate to heavy rainfall is possible, especially in terrain and poor drainage areas. * WHERE...Portions of central, north central, and northwest Wyoming, including the following areas, in central Wyoming, Owl Creek and Bridger Mountains. In north central Wyoming, Bighorn Mountains Southeast, Bighorn Mountains West, Northeast Johnson County and Southeast Johnson County. In northwest Wyoming, Absaroka Mountains, Cody Foothills and Yellowstone National Park. * WHEN...Through Sunday afternoon. * IMPACTS...Excessive rainfall may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Flooding may occur in poor drainage and urban areas and around steep terrain. * ADDITIONAL DETAILS... - A slow moving weather system will move across Wyoming today through Sunday and bring rounds of showers and thunderstorms to the region, especially northern Wyoming. Any shower or thunderstorm could produce moderate to heavy rainfall across the Watch Area. - http://www.weather.gov/safety/flood |
| Alert: | Flood Watch |
| Area(s): | Musselshell; Treasure; Northern Rosebud; Custer; Northern Stillwater; Powder River; Northern Park; Golden Valley; Red Lodge Foothills; Northern Big Horn; Southern Rosebud; Judith Gap; Paradise Valley; Livingston Area; Beartooth Foothills; Absaroka/Beartooth Mountains; Crazy Mountains; Southern Big Horn; Southeastern Carbon; Northern Sweet Grass; Bighorn Canyon; Northern Carbon; Pryor/Northern Bighorn Mountains; Melville Foothills; Northeastern Yellowstone; Southern Wheatland; Southwestern Yellowstone; Northeast Bighorn Mountains; Sheridan Foothills |
| Effective: | 2026-09-18 @ 11:59 pm -> 2026-09-20 @ 12:00 am |
| Onset: | 2026-09-18 @ 11:59 pm -> 2026-09-20 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Billings MT on 2026-09-18 @ 11:59 pm |
| Headline: | Flood Watch issued September 18 at 10:59PM MDT until September 20 at 6:00PM MDT by NWS Billings MT |
| Description: |
* WHAT...Flooding caused by excessive rainfall is possible, along with Flash Flooding of recent burn scars. * WHERE...All of South Central and Southeast Montana, and Sheridan County Wyoming. * WHEN...Through Sunday afternoon. * IMPACTS...Excessive runoff may result in flooding of creeks and other low-lying and flood-prone locations. Flooding may occur in poor drainage and urban areas. * ADDITIONAL DETAILS... - 1 to 3 inches of additional rainfall is expected across the watch area through Sunday. Locally heavier totals over 4 inches are possible where thunderstorm activity is more persistent. - The Robertson Draw, East Side, Elk, and McGhee-Remington burn scars are particularly vulnerable to Flash Flooding and debris flows during the watch period. Any other burn scars from this summer will have elevated Flash Flood potential as well. - http://www.weather.gov/safety/flood |
| Alert: | Hydrologic Outlook |
| Area(s): | Big Horn, WY; Fremont, WY; Hot Springs, WY; Johnson, WY; Lincoln, WY; Natrona, WY; Park, WY; Sublette, WY; Sweetwater, WY; Teton, WY; Washakie, WY |
| Effective: | 2026-09-18 @ 11:20 am -> 2026-09-19 @ 1:00 pm |
| Onset: | 2026-09-18 @ 11:20 am |
| Severity: | Unknown |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Riverton WY on 2026-09-18 @ 11:20 am |
| Headline: | Hydrologic Outlook issued September 18 at 10:20AM MDT by NWS Riverton WY |
| Description: |
ESFRIW A wet weather system will support periods of showers and thunderstorms across Wyoming Friday, Saturday, and Sunday. This weather system is funneling abundant tropical moisture into the state. Given this anomalously high moisture, many thunderstorms will feature heavy rainfall, possibly leading to localized flooding. Poor drainage areas, urban areas, and steep terrain will be the most susceptible locations for this isolated flooding. Many locations could see rainfall totals anywhere between 0.75" to 1.75" through Sunday afternoon, with a majority of this rain falling quickly in thunderstorms. Remember, if you encounter a flooded roadway, turn around don't down! |
