Runoff from a combination of heavy rain and some mid elevation snow melt may cause flooding of streams and low lying areas in and downstream of the foothills. Moderate to heavy rainfall over recent burn areas (Robertson Draw and American Fork) may produce flash flooding in and downstream of the burned area. * WHAT. Flooding caused by rain and snowmelt remains a threat. * WHERE. Portions of south central Montana, including the following areas, Bighorn Canyon, Pryor/Northern Bighorn Mountains and Southern Big Horn and north central Wyoming, including the following areas, Northeast Bighorn Mountains and Sheridan Foothills. * WHEN. From this evening through Monday evening. * IMPACTS. Excessive runoff may result in flooding of streams and other low-lying and flood-prone locations close to the foothills. Some roads may become impassable. Now is the time to move equipment and livestock to higher ground away from waterways. Recent burn scars may be more susceptible to produce flash flooding, including the Elk burn scar west of Dayton and Sheridan. * ADDITIONAL DETAILS. - Scattered showers and thunderstorms this evening will turn to more persistent rain into the overnight hours. Snow levels will fall from 9500 feet this evening to around 5000 feet Monday morning. Rain falling on snow may melt 1 to 3 inches of snow water before cooler temperatures change precipitation to snow in the foothills, ending the snowmelt. The combination of precipitation and snowmelt may result in a 2 to 4 inch water event with rapid runoff filling small streams and creeks along the foothills. - http://www.weather.gov/safety/flood
