While there was a fog layer near the ground this morning, air monitoring stations were reporting air quality within the “GOOD” range. But by late morning, things began to change.
Before noon today, air quality reported from the Northwest Clean Air Agency’s air monitoring station on Loomis Road in Custer jumped from “GOOD” to “MODERATE” and into the “UNHEALTHY FOR SENSITIVE GROUPS” zone (see graphic above).
This morning, Washington Department of Ecology officials via the Washington Smoke Information blog said, “A shift in winds over the weekend brought a thick haze from Canada that is covering most of our state. Fortunately, residents in Western Washington are still experiencing Good air quality, with the exception being places at higher elevations in the Cascades experiencing air quality that is Unhealthy for Sensitive Groups. Some smoke might make its way from Canada into the Puget Sound lowlands later today and tomorrow, but westerly winds should return on Wednesday and clear out any lingering smoke.”
According to a special statement issued about 4pm by the Nation Weather Service (NWS) Seattle office today, “Smoke from surrounding wildfires may result in poor air quality this afternoon through Tuesday.”
The Northwest Clean Air Agency also noted this afternoon, “Smoke is coming into the area rapidly,” and “Monitors are showing smoke particles in the ‘Unhealthy for Sensitive Groups’ range in Bellingham, the Lynden/Custer area, and downtown Anacortes, plus ‘Unhealthy’ in Columbia Valley near Kendall.”
NWS forecasters say an upper level high pressure and offshore surface flow have allowed for the smoke to drop into the lower atmosphere.
The situation isn’t expected to improve until late Tuesday night and Wednesday as surface flow shifts onshore. Until then, conditions are expected to stay the same or possibly worsen in some areas.
Washington Department of Ecology official say when air quality is reported in the UNHEALTHY FOR SENSITIVE GROUPS range more people than average may have breathing problems or have worsened symptoms of existing asthma or lung disease. Sensitive groups include people with heart or lung disease, asthma, diabetes, infants, children, adults older than 65, pregnant women, or who have had a stroke. These people are advised to limit time spent outdoors.