Yet another hazy horizon greeted Sacramento-area residents Thursday morning, with a Spare the Air advisory extended for the region.
The advisory marked the 16th designated Spare the Air day of the year, nearing the 17-day total for 2017. The Sacramento Metropolitan Air Quality Management District urged residents in its advisory to reduce driving, limit outdoor activity and be aware of unhealthy air quality conditions for sensitive groups through Thursday.
Smoke from several large wildfires across Northern California continues to spread into the greater Sacramento region. Combined with ozone-producing cloudless skies and warm temperatures, air quality conditions look like they will remain unhealthy for sensitive groups for Sacramento County through at least Monday, according to the air district’s forecast.
Wednesday’s air quality index for the region reached a high of 195. An AQI reading of 151 is the minimum threshold for a determination of unhealthy for everyone.
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Despite the gloom, air quality conditions Thursday morning were relatively good in downtown Sacramento, with an ozone AQI of 4. However, PM2.5 levels continue to hover in the moderate range at an AQI of 55, the Spare the Air website said. PM2.5 refers to atmospheric particulate matter (PM) with a diameter of less than 2.5 micrometers, small enough to pass through the lungs.
Morning conditions remained moderately poor to unhealthy in Folsom, Auburn, Colfax and Grass Valley as of 9 a.m. Thursday.
The Sacramento region’s Spare the Air program runs from May to October every year.