Wyoming Unknown Hydrologic Outlook | Effective 09/19/2026 10:59

ESFRIW Periods of showers and thunderstorms are expected across the northern half of Wyoming Saturday and Sunday as a wet weather system shifts east across the state. This weather system is funneling abundant tropical moisture into northern and eastern portions of the state with it's eastward progression. Given the high moisture content, many thunderstorms could feature heavy rainfall and possibly lead 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 an additional 0.5" to 1.25" of rain 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!