Winter Weather in Southwest Interior, Washington

A stretch of winter weather affected the Southwest Interior at the beginning of December. On Dec 1, an average of 1-2 inches was reported (highest report of 3.5 inches), on Dec 2 an average of 0.5-1 inch was reported, and an average of 1-3 inches was reported on Dec 3.

A period of wintry weather was noted across the Western Washington lowlands at the beginning of December, earlier than what is typically experienced. Snow began at the end of November with several rounds continuing through the first few days of September. While accumulations did not meet winter storm criteria Dec 1-2, widespread heavy snow accumulations were experienced on Dec 3. These conditions were largely due to Fraser outflow in the low levels. with deep upper troughing in the upper levels.