An atmospheric river will bring moderate rain rates to the mountains of western Montana through Saturday afternoon. This will fall on a deep primed snowpack leading to the melt increasing. Flows in rivers and streams may increase and reach bankfull or exceed their banks.
What: Flooding caused by rain and snowmelt continues to be possible.
Where: A portion of northwest Montana, including the following county, Lincoln.
When: Through Sunday morning.
Impacts: Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Creeks and streams may rise out of their banks. Flooding may occur in poor drainage and urban areas. Low-water crossings may be flooded. Rockfall is possible.
Additional Details: - The atmospheric river will bring moderate rain rates between 0.10 to 0.25 inches per hour to the Cabinet Mountains between 9 PM Friday evening and 4 AM MDT Saturday. With conditions already primed, creeks could overflow their banks early Saturday morning. Landslides and rockfalls are possible on windward and leeward sides of the mountains. Ross Creek has swelled into nearby ditches and caused water to flow over Highway 56 south of Bull Lake. The Yaak River and Fisher River are forecast to reach action stage by Saturday night. - https://www.weather.gov/mso/hydrology