Flood — Benewah, Idaho

2012-03-31 · near Riverdale, Benewah, Idaho

Event narrative

The Saint Joe River at Saint Maries rose above the flood stage of 32.5 feet at 0300 PDT on March 31st, crested at 33.9 feet at 0600 PDT on April 1st, and receded below flood stage 2100 PDT on April 3rd. Saint Joe City Road flooded. Minor flooding was observed throughout low lying areas of the Saint Joe Valley and of the Aqua Park in Saint Maries.

Wider weather episode

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.

View location on OpenStreetMap → (47.3152, -116.5550)

Source: NOAA Storm Events Database, event_id 368948. Narrative written by the NWS forecast office that issued the report.