Debris Flow in Lewis and Southern Nez Perce, Idaho

A mudslide partially blocked Highway 12 between mile marker 49 and 50.

A stagnant longwave pattern featuring a broad trough off the Pacific Northwest Coast and upper-level ridge over the Central US resulted in a parade of moist storm systems tracking through the Inland Northwest from March 28th through the 31st. Each storm system deposited 0.25 to 0.75 inches of rainfall across most locations in the Idaho Panhandle with three day rainfall totals ranging from one to three inches. This concluded record setting precipitation totals for the month of March. With soils already saturated from heavy rain just a few days earlier and above normal snowpack still in place in the mountains, portions of North Idaho experienced numerous floods, road washouts, and debris flows. The most significant damage occurred in Bonner County which involved a train track washout, train derailment, and washout of a hundred foot length of road near Cocolalla Lake.