* WHAT...Flooding caused by excessive rainfall is possible. * WHERE...Portions of central and south central Montana, including the following areas, in central Montana, Golden Valley, Judith Gap, Musselshell and Southern Wheatland. In south central Montana, Crazy Mountains, Melville Foothills, Northeastern Yellowstone, Northern Stillwater, Northern Sweet Grass and Southwestern Yellowstone. * WHEN...From Tuesday afternoon through Tuesday evening. * IMPACTS...Excessive runoff may result in flooding of creeks, streams, and other low-lying and flood-prone locations. Flooding may occur in poor drainage and urban areas. * ADDITIONAL DETAILS... - Scattered thunderstorms with the potential to produce very heavy rainfall will move across the area late Tuesday through the evening. - http://www.weather.gov/safety/flood