The Thomas fire in Ventura County had grown to 115,000 acres and was at just 5 percent containment, officials announced Thursday evening as the blaze entered its fourth night of destruction.

The fire was still threatening areas of southern Santa Barbara County at 6 p.m. Thursday after it had already destroyed 427 structures and damaged 85 others in Ventura County. More than 2,600 firefighters — including local crews and some from as far away as Oregon and Nevada — were on scene battling the raging blaze.

An hour after Santa Barbara County public health officials issued air quality warnings for Santa Barbara to Lompoc, the Santa Barbara County Sheriff’s Office issued mandatory and voluntary evacuation orders for parts of the city of Carpinteria, Summerland and unincorporated areas of Santa Barbara County effective 6 p.m. Thursday.

Although Santa Ana winds are expected to weaken Friday, that isn’t necessarily a good sign for firefighters, according to Tim Chavez, a fire behavior analyst working with the incident management team.

“A fire that’s burning under a strong Santa Ana condition, even though it moves very rapidly with very high intensity, it’s very predictable (and) we know exactly where it’s going because the wind is pushing it over terrain (and) over any kind of fuel features in one direction,” Chavez said Thursday evening.

“Well, now that Santa Ana weakening is gonna cause the fire to be much less predictable," he continued. "It’s gonna move in a different direction and it’s gonna be terrain-driven, so crews are gonna have to be very careful on their position when those transitions happen, and sometimes those can be very difficult to predict.”

The mandatory evacuations in Santa Barbara County included the area of Highway 192 north of Highway 150 to Cravens Lane. That area had previously been under a voluntary evacuation warning, but officials wanted people out of the region in case the fire took an unpredictable turn in that direction.

Previous mandatory evacuation orders remained in effect for areas of Highway 150 from Rincon Hill Road south to Highway 101, including Bates Road and the area of Rincon Point.

As the fire raged south of the Santa Barbara County border, its effects were felt in the North County.

County public health officials reported Thursday that the air quality index showed worsening air quality in Santa Barbara County, including “hazardous” levels in Santa Barbara, “very unhealthy” levels in Goleta and “unhealthy” levels in Lompoc.

"With the Thomas fire continuing to burn, we anticipate continued concerns about air quality,” read a portion of a release sent just after 10 a.m. Thursday by the Santa Barbara County Public Health Department. “N95 masks, when fitted properly, offer some limited protection from fine particles in smoke. Dust masks and surgical masks are not effective.”

In light of the poor air quality, county officials are recommending that residents:

  • Stay indoors, with windows closed and indoor circulation only. Air conditioning is also an option if the outside intake is closed. Avoid going outdoors. Particles can build up indoors, so if you are feeling symptoms where you are be prepared to relocate to an indoor location with better ventilation, or to leave the area.
  • Avoid driving when possible and use “recycle” or recirculate mode to avoid drawing smoky air into the car.
  • Drink plenty of fluids to keep respiratory membranes moist.
  • Avoid doing anything to stir up ash.

“It is especially important for people with lung and heart conditions to stay indoors, and to consider leaving the area while the air quality index is ‘very unhealthy,’” according to county public health officials. “If able, relocate to an area not impacted by smoke.”

For individuals who have to be outdoors for short periods of time:

  • The cities of Goleta, Santa Barbara and Carpinteria will be distributing N95 masks to individuals who need them. A maximum of two per person will be provided.
  • There are not enough masks to provide one for everyone in the South County, officials report. These masks are best for those with sensitivities who have to be outdoors for short periods of time. These masks do not filter out all of the harmful gases. They must also fit properly to be effective.
  • Carefully read and follow the proper instructions to create a fitted seal around the nose and mouth.
  • N95 masks do not come in sizes suitable for small children. All children, and especially those with asthma or other chronic health conditions, should avoid outdoor activity that would expose them to breathing in smoky air for extended periods of time.
  • People who use inhalers for asthma or other conditions should make sure they have access to their inhaler, and refill prescriptions if necessary.
  • People who have respiratory conditions should talk with their doctors about use of masks, as they reduce airflow.

The N95 masks will be available beginning at 10 a.m. Friday at the Goleta Costco, 7095 Market Place Drive; at the Franklin Community Center, 1136 E. Montecito St. in Santa Barbara; and at Albertsons, 1018 Casitas Pass Road in Carpinteria.

The Santa Barbara County Public Health Department and the Santa Barbara County Air Pollution Control District emphasized Thursday that the air quality warning for Santa Barbara County will remain in effect until conditions improve.

Smoke and ash from the Thomas fire may continue to affect local air quality for days, officials reported. Levels of smoke and particles, and areas impacted, including potentially other areas of the county, will vary, and conditions could change quickly.

Due to the fire, the following Santa Barbara County public school districts have announced closures for Friday:

  • Carpinteria Unified School District
  • Cold Spring School District
  • Goleta Union School District
  • Hope Elementary School District
  • Montecito Union School District
  • Santa Barbara Unified School District
  • Vista del Mar Union School District

Additionally, Santa Barbara City College, Westmont College, Peabody Charter School, Santa Barbara Charter School, Cate School, Santa Barbara Middle School and Laguna Blanca School also have announced they will be closed Friday.

For current air quality conditions, check www.OurAir.org/todays-air-quality/. The chart will indicate when air quality is good, moderate, unhealthy for sensitive groups, unhealthy for all, very unhealthy and hazardous.

For more information, also see www.airnow.gov/index.cfm?action=smoke.index.

Willis Jacobson covers the city of Lompoc for Lee Central Coast Newspapers. Follow him on Twitter @WJacobsonLR.

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