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. Burn Scars 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 9 PM MDT 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. Elk Burn Scar is susceptible to flash flooding. * ADDITIONAL DETAILS. - Scattered showers and thunderstorms this evening will turn to more persistent rain and snow in the higher foothills and mountains in the overnight hours. The combination of precipitation and snowmelt may result in a 1 to 3 inch water event with rapid runoff filling small streams and creeks along the foothills. - http://www.weather.gov/safety/flood