Air Quality Index readings

From Bay Area Air Quality Management District

When "Moderate" Air Pollution Seems Good

Shift in Weather Ends Smoke Siege

KCBS Radio Morning News
November 21, 2018 - 6:28 am

SAN FRANCISCO (KCBS Radio) -- For the first time in nearly two weeks, air quality readings in much of the Bay Area dropped from "hazardous" and "unhealthy" to lesser categories on Wednesday morning.

While pockets of air considered "unhealthy" remained in places like Vallejo, Pleasanton and Livermore, one Bay Area Air Quality Management District gauge showed "good" air quality in San Jose. Readings in San Francisco, the East Bay and on the Peninsula fell into the "moderate" air pollution category (Air Quality Index between 51 and 100).

The declining levels of particulate pollution generated by the massive Camp Fire in Butte County were driven by winds preceding an expected storm system.

The National Weather Service predicted anywhere from a half-inch to 2.5 inches of rain will fall over the Bay Area between Wednesday and Friday.

That rain will end a record-setting dry spell in some places. It has been 223 days since Oakland International Airport recorded more than a tenth of an inch of rain on a single day, the longest such stretch on record. San Jose has gone 218 days without recording a 24-hour rainfall total of a tenth of an inch or more.