Dense Smoke — Washington Palouse, Washington

2020-09-12 to 2020-09-19 · Washington Palouse, Washington

Event narrative

An air quality sensor in Pullman recorded unhealthy air quality from September 12th through September 19th. It spiked to continuous hazardous conditions on September 13th through 15th. The arrival of a cold front on September 19th brought showers and westerly winds which ventilated the area.

Wider weather episode

Multiple large wildfires in Washington, Oregon, and surrounding states produced copious quantities of dense smoke throughout the month of September. Due to poor ventilation and a gradual return to southwest winds, there were increasing amounts of wildfire smoke to Washington. The smoke from these fires severely degraded air quality across much of eastern Washington in mid-September. Numerous communities, especially in the Spokane area, suffered long periods of very unhealthy to hazardous air quality.

Source: NOAA Storm Events Database, event_id 922092. Narrative written by the NWS forecast office that issued the report.