Flood — Flathead, Montana

2016-05-22 to 2016-05-24 · near Columbia Falls, Flathead, Montana

Event narrative

Between 4 to 6 inches of rain fell within 24 hours causing Spoon and Duck lakes to spill out onto Lake Drive and North Fork Road, and ending up near the Blankenship Road intersection as culverts were unable to handle the extra runoff. Rabe Road also experienced flooding from water originating from the Tea Kettle Mountain area. A private sensor located east-northeast of the Tea Kettle North Mountain or about 3 miles northwest of Coram, measured 6.29 inches of rainfall. The flooding closed North Fork Rd and Rabe Rd which impacted 25 to 30 residents. At least fifteen structures including basements and shop garages were flooded. One unfinished garage saw water that rose to near the ceiling. A fire chief with the Blankenship Fire Department who lives just off of North Fork Road outside of Columbia Falls reported that over three thousand gallons of water flooded his finished basement during this event. On May 23rd, more intense rain developed just north of Columbia Falls resulting in Trumble Creek coming out of its banks. This placed water around seven homes, but did not cause much damage or prevent residents from access. Glacier National Park closed the Going-to-the-Sun-Road at the Apgar Loop Junction due to a culvert washout in the afternoon of May 23rd. Another reason why the culvert was overwhelmed was due to beaver dams breaking up higher in the drainage. At least two portions of the Forest Service road 895 past the Hungry Horse Dam were washed out on May 23rd including Beta Creek. Forest service road 316 from the 6.3 mile marker on North Fork Road to the Canyon Creek area also experienced several washouts.

Wider weather episode

A slow moving closed low pressure system tracked from Oregon north and east across northwest Montana into southern Alberta from May 21st to May 22nd. This system most likely tapped into Gulf of Mexico moisture that had been pooling up over the High Plains and dropped 4 to 6 inches of rainfall to the mountains near Columbia Falls and Glacier National Park. This heavy rainfall caused area lakes and streams to overflow and flood nearby roads and land surrounding a few homes. This event also contributed to the West Glacier cooperative observer at Glacier National Park to report a record high precipitation total of 6.40 for the month of May, with records going back to 1949.

View location on OpenStreetMap → (48.3700, -114.1800)

Source: NOAA Storm Events Database, event_id 634479. Narrative written by the NWS forecast office that issued the report.