Heavy Rain in King County, Washington

Heavy rain on top of saturated soils triggered a landslide that knocked a house off it's foundation, collapsing one level - destroying it and trapping the inhabitants. One man was trapped under debris and injured and had to be extricated by Seattle Fire Department. A woman was also pinned under debris but was able to escape. One dog was killed and another was found a week later in the debris and extricated. At the time, 1 to 2 inches of rain had fallen in the area in the previous 48 hours with the Seattle Antecedent Rainfall Index already high, above the threshold for heavy rain-induced landslides.

A strong and persistent upper-level low-pressure system developed over the northern Rockies and southern Canada and then slowly migrated westward while continuously directing the jet stream and primary storm track at Washington State. This strong low-pressure system resulted in a 21-day period of a series of winter storms, wind storms, and atmospheric rivers that battered Washington State in rapid succession. First there was lowland snow the last week of December. Then a wind and rainstorm Jan 3 to 4. That was followed by two atmospheric river events from Jan 5 - 7 and Jan 11- 13 that resulted in heavy rain, minor to major flooding, and landslides. 2 flood fatalities occurred, and possibly a third from a landslide.