U.S. Air Quality

Fires in Oregon Producing Heavy Smoke

The Boze and Tumblebug Complex fires in southwestern Oregon grew today and are now producing dense smoke plumes. The location of the fires and smoke can be seen in today's MODIS Terra true color image (below on left, overlaid with current AQI values in Google Earth). According to the National Interagency Fire Center, the Boze fire is burning 2,100 acres with 35% contained, and the Tumblebug Complex fire is burning 1,500 acres with only 10% contained. The National Weather Service in Portland has issued a Red Flag Warning for the North and Central Oregon Cascades and Foothills and the South Washington Cascades and Foothills effective until 5 PM PDT Wednesday, so it seems probable that the fires will continue to grow over the next 24 hours. A ridge of high pressure aloft will keep a very dry and warm airmass over the region until late Wednesday, which will maintain conditions favorable for explosive fire growth. Although air quality at the surface is likely very poor in the vicinity of the fires, the closest PM2.5 monitors are currently measuring Code Green (Good) and Code Yellow (Moderate) conditions, which suggests that they are too far away to measure the impact of the fires. Today's MODIS Terra AOD image for Region 10 (below on right) indicates that AOD levels are high due to particulates in the smoke from the fires.

Elsewhere, PM2.5 air quality was mostly in the Code Green range, with a few areas of Code Yellow in the Great Lakes and California, as shown in today's loop of PM2.5 AQI values (below on left). Ozone was Code Green except for California (below on right), where levels reached Code Orange (Unhealthy for Sensitive Groups) in central portions of the state.