Residents living in at least 1,300 homes have been forced to evacuate parts of Missoula city, Montana after flooding hit the area. | AccuWeather

When the Missoula floods surged into the Snake River, they backflooded 150 miles upstream, leaving fine silts at the distal reach. At the same time, the Bonneville flood thundered north through Hell’s Canyon, dropping massive boulders at its mouth. At Tammany Bar, the two torrents met —coarse Bonneville gravels overlying Missoula silts —a geological record of cataclysms colliding. | The Randall Carlson