Flash Flood — Hot Springs, Wyoming

2015-05-24 to 2015-05-25 · near Thermopolis, Hot Springs, Wyoming

Event narrative

Very heavy rain fell in southern Hot Springs County. This triggered numerous mud and rock slides, some tumbling several hundred feet or more to the bottom of the Wind River Canyon. State Highway 789 through the canyon was covered with mud, rock, and debris in several locations between mileposts 120 and 123. One Wyoming Department of Transportation employee was briefly trapped in his front-end loader as he tried to clear away small slides at the onset of the event. The massive amount of debris on the highway resulted in the closure of the road from Sunday afternoon, May 24, until Wednesday morning, May 27. Additional slides on the west side of the Wind River Canyon destroyed several sections of railroad track that resulted in a halt of train traffic for several days.

Wider weather episode

A slow-moving upper level low south of Wyoming sent waves of moisture northward over central and eastern Wyoming during the Memorial Day holiday weekend. Measured and estimated rainfall totals ranged from two to around five inches. This resulted in flooding and flash flooding in several areas. Johnson County saw significant flooding along the tributaries and main stem of the Powder River and around Buffalo. The greatest impact was felt in Hot Springs County where heavy rains in the Wind River Canyon resulted in several mud and rock slides that closed State Highway 789 between Thermopolis and Shoshoni. The slides also damaged several sections of railroad track in the same area subsequently shutting down rail traffic. Minor flooding was also noted in Fremont County where water approached homes in low lying areas of Lyons Valley near Lander.

View location on OpenStreetMap → (43.5413, -108.1968)

Source: NOAA Storm Events Database, event_id 571080. Narrative written by the NWS forecast office that issued the report.