Northern California wildfire smoke clouds Sonoma County skies

Smoke from numerous Northern California wildfires invaded the Bay Area on Thursday, obscuring the hills and turning the air into a chalky yellow haze just as temperatures spiked from a statewide heat wave expected to last through the Labor Day weekend.

The smoke was an unwelcome accompaniment to extreme weather expected to produce the hottest days of this summer so far, and potentially the warmest since 2006.

“There is an excessive heat warning all the way through the holiday weekend,” said National Weather Service forecaster Duane Dykema. “The heat is going to reach all the way to the coast, or very close to it. It’s a little different than what we’ve seen this summer.”

He said the high-pressure ridge is affecting the entire West Coast and the western third of the country with accompanying heat warnings and advisories.

Meanwhile winds out of the north were pushing smoke into the Bay Area from more than a dozen fires in Northern California and southern Oregon, including the Chetco Bar fire currently burning 128,700 acres in the Rogue River-Siskiyou National Forest.

“Lake County, the Bay Area, down to the city - everyone’s impacted and everyone’s calling about it,” said Cal Fire spokeswoman Suzie Blankenship, who said the smoke is likely to stick around. “This isn’t going to clear up in a day. It takes a little while to clear.”

The closest and most active fire at the moment is in Trinity County, where Cal Fire is helping fight a blaze in the Six Rivers National Forest east of Zenia. Blankenship said.

Dykema said it looks like shifting winds could bring some relief from the itinerant smoke. “There’s a pretty good chance it will become less noticeable,” he said. “I don’t think it will disappear entirely. It will linger for a few days at least.”

The Bay Area Air Quality Control District said ozone levels will be unhealthy for sensitive groups. Active children and adults, and people with respiratory disease, such as asthma, should limit outdoor exertion.

Meanwhile, the Weather Service was predicting a high of 106 today for Santa Rosa and 107 Saturday. Elsewhere, temperatures were set to spike even higher, topping out today at 115 in Sonoma and 109 in Cloverdale.

The projected highs are about 20 degrees higher than normal for this time of year.

“We will see relief starting Sunday into Monday,” Dykema said. “Temperatures will begin to moderate on those days. It will still be very hot through the weekend.”

An excessive heat advisory remains in effect through Monday at 9 p.m. for interior valley and higher elevations in the Bay Area, according to the National Weather Service.

It’s good that residents are paying close attention to fire risks given the heat wave gripping the region, Blankenship said. The hot, dry, windy conditions have prompted the state agency to issue a red flag warning for extreme fire danger in many coastal mountain areas through Saturday morning.

Air quality officials said the degraded air quality is the result of ultra fine particulates and other air pollutants contained in wildfire smoke combined with the high temperatures and low humidity.

Individuals with asthma, bronchitis, emphysema and other lung or heart diseases are advised to carefully adhere to their medical treatment plans and maintain at least a five-day supply of prescribed medications.

Air conditioning and drinking water to avoid drying airways can also provide some respite.

Staff Writer Kevin McCallum contributed to this story.