The air will remain stagnant in the valleys of Southern Oregon and Northern California for much of this week.
The National Weather Service has posted an Air Stagnation Advisory for the region that runs until at least 10 a.m. Thursday.
Poor mixing and weak winds mean that stagnant air is expected, which may lead to deteriorating air quality. The air stagnation is likely to result in diminishing air quality especially in and near areas with significant sources of pollution.
Poor air quality is likely to cause health issues for people with respiratory problems if precautions are not taken. People with respiratory illness should follow their physician's advice for dealing with diminished air quality.
State air quality agencies highly recommend that no outdoor burning occur and that residential wood burning devices be limited as much as possible. Prolonged periods of stagnant air can hold pollutants close to the ground where people live and breathe. Check with your local burn agency for any current restrictions.
