An air quality advisory prompted by smoke from a major Los Angeles commercial fire has been extended through Thursday night, Nov. 12, with Hawthorne among the communities named in the updated warning.

The National Weather Service relayed South Coast Air Quality Management District’s extension at 11:29 a.m. Wednesday, Nov. 11. The advisory lasts until 11:59 p.m. Thursday.

The updated bulletin names Vernon, Maywood, Bell Gardens, Westmont, Hawthorne, Inglewood, downtown Los Angeles, East Los Angeles and Huntington Park. Manhattan Beach was named in Tuesday’s bulletin but is not specifically listed in Wednesday’s update.

Pollution levels can vary by location and time depending on emissions and weather conditions.

What's driving the smoke

Firefighters were called around 1:02 a.m. Monday, Nov. 9, near South Alameda Street and East 55th Street in the Central-Alameda neighborhood, according to the LAFD. About 200 LAFD firefighters, assisted by Los Angeles County Fire crews, responded to a 100-by-150-foot commercial building fully engulfed in flames.

The building is one of four connected structures housing an industrial flooring business that specializes in hardwood and cork materials, according to the LAFD. The fire spread into an adjoining two-story, metal-clad building.

Crews declared knockdown at 5:24 a.m. that morning, four hours and 22 minutes after the initial 911 call. But large quantities of palletized storage concealed pockets of fire. The LAFD deployed heavy equipment and its RS3 firefighting robot to pull apart burning materials.

A flare-up around 4 a.m. Tuesday prompted several additional fire companies to be attached to the incident, according to the LAFD. The department said overhaul operations could continue for several days.

In a Wednesday morning update, LAFD said crews were working to reduce smoke and make the area safe for utility workers to repair damaged lines and restore power.

What residents should do

Air quality sensors southwest of the fire recorded a brief period of unhealthy concentrations of fine particulate pollution, known as PM2.5, on Tuesday morning, according to the South Coast AQMD as reported by Patch. Overnight winds could push smoke farther southwest toward Manhattan Beach and Hawthorne, the agency said.

The NWS alert ties recommended actions to Air Quality Index (AQI) levels. At the "Unhealthy for Sensitive Groups" level, people with lung or heart disease, older adults, pregnant people, children and those who spend extended time outdoors should limit intense outdoor activity. At the "Unhealthy" level, everyone may experience health effects, and sensitive groups should avoid extended time outdoors. The full AQI guidance is available in the NWS alert.

The alert also recommends keeping windows and doors closed, running air conditioning or an air purifier, and avoiding fireplaces, candles, grilling and gasoline-powered lawn equipment. Residents who use swamp coolers or whole-house fans that draw outside air should switch to other cooling methods.

Ash may also settle across affected areas. Standard AQI monitors do not account for large ash particles, according to the LAFD.

Residents can check real-time conditions at the South Coast AQMD website, aqmd.gov.