Winter Storm — Lower Chehalis Valley Area, Washington

2021-02-12 to 2021-02-13 · Lower Chehalis Valley Area, Washington

Event narrative

Significant snowfall impacted the Lower Chehalis Valley beginning during the late afternoon and early evening hours of February 12 and continuing through the overnight period into February 13. Snowfall amounts during this general timeframe ranged from between 5-9 inches. Snow gradually tapered into the afternoon hours on February 13, with little additional snowfall accumulation thereafter.

Wider weather episode

A significant snowstorm impacted the lowlands of Washington beginning during the evening hours of February 12 and continuing through the morning of February 13. Strong Fraser outflow was responsible for the advection of much colder air west of the Cascade Crest. As this cold air entrenched the Western Washington lowlands, a strong storm system was approaching from off the Pacific, bringing with it sufficient moisture towards the area. The low made landfall near the mouth of the Columbia River during the early morning hours of the 13th, which was the prime location to allow for significant snowfall over Western Washington. Heavy snowfall accumulated quickly overnight and continued through the morning of the 13th before tapering during the afternoon and evening.

Source: NOAA Storm Events Database, event_id 945686. Narrative written by the NWS forecast office that issued the report.