California wildfires latest: Santa Barbara County fire grows to over 38,000 acres

"It's scary," said Raymond Williams, whose home is in the area of the Lake Fire.

The largest blaze of the California wildfire season, the Lake Fire in Santa Barbara County, grew to over 38,000 acres by Friday, fueled by gusty winds and extreme temperatures, authorities said.

The Lake Fire burning near the Los Padres National Forest has charred over 38,000 acres of mostly grassland and timber, and grew substantially throughout the week.

On Friday, Cal Fire said the wildfire was at 19% containment, an improvement from 16% earlier in the day.

The cause of the Lake Fire, which began on July 5, remains under investigation, according to officials.

"It's scary," Raymond Williams, a lifelong resident of the area, told ABC News earlier this week as he monitored the direction of smoke and flames burning in the hills near his home. "I know a lot of people that live around the area, a lot of families live around here. I hope they can keep structures safe."

The Lake Fire is one of 19 wildfires burning in California as of Wednesday, Cal Fire said.

The wildland blaze about 40 miles north of the city of Santa Barbara started on Friday afternoon near Zaca Lake in the Los Padres National Forest.

The Santa Barbara County Sheriff's Department issued evacuation orders on Saturday night as the blaze grew out of control. The evacuation orders, which remained in place Wednesday, included the 5000 block of Figueroa Mountain Road, where Michael Jackson's former ranch is located, officials said.

Warnings were also issued for residents in the surrounding area to be prepared to evacuate, according to the sheriff's office.

"Significant fire activity on the southeast side of the fire footprint has prompted additional evacuations and an increase in acreage," Cal Fire said in an updated statement on Wednesday.

The wildfire erupted during a heat wave that has enveloped the area and most of California.

The fire grew rapidly over the last few days as temperatures have soared into the high 90s with a relative humidity of around 11%.

"When relative humidity decreases, fire behavior increases because fine fuels like grass and pine needles become drier quickly," according to the Western Fire Chiefs Association (WFCA).

North Fire

The North Fire, which broke out Sunday afternoon in Northern California, west of Mt. Shasta near the Oregon border. The North Fire in Modoc County, fueled by dry rangeland grasses, has spread to 4,389 acres and was 60% contained on Wednesday, according to Cal Fire.

The Modoc County Sheriff's Office issued mandatory evacuation orders for homes and businesses in the path of the fire, including the communities of West Valley, Wormville and Mill Creek Falls.

Shelly Fire

A Northern California wildfire burning out of control Wednesday was the Shelly Fire in Siskiyou County, also near the Oregon border, according to Cal Fire. The fire, which started on Sunday in the Klamath National Forest near Lake Shelly and the Pacific Crest Trail, had burned 8,285 acres as of Wednesday and was 0% contained, according to Cal Fire.

The Siskiyou County Sheriff's Office issued mandatory evacuation orders to residents in the path of the fire and warned others to be prepared to flee.

Basin Fire in San Joaquin Valley

The most stubborn fire in the state, the Basin Fire burning in the foothills east of Fresno in the San Joaquin Valley, was 85% contained on Wednesday after burning 14,027 acres, according to Cal Fire. The blaze started on June 26 in the Sierra National Forest north of Pine Flat Lake and south of Shaver Lake and Wishon Reservoir.

The cause of the fire remains under investigation.

Temperatures in the area of the Basin Fire are forecast to remain in triple digits throughout the week.

French Fire near Yosemite National Park

The French Fire near Yosemite National Park in Mariposa County has burned 908 acres since erupting Thursday and was 80% contained as of Wednesday, according to Cal Fire.

Three firefighters were injured battling the wildfire, which has destroyed four structures, Cal Fire said.

McCain Fire in San Diego County

Another significant Southern California fire is the McCain Fire, which started on July 1 in southeast San Diego County.

As of Wednesday, firefighters had the fire almost completely extinguished, having achieved 95% containment on the blaze that has burned 1,595 acres.

Royal Fire

The Royal Fire had burned 215 acres in Northern California's Placer County as of Wednesday, according to Cal Fire. The fire was 15% contained on Wednesday.

Earlier this week, 13 hikers stranded in a wildfire zone near the Tahoe National Forest were rescued, authorities said.

The Placer County Sheriff's Office launched a search for the hikers after finding their vehicles within the area where the Royal Fire ignited around 4 p.m. on Sunday.

A search-and-rescue helicopter crew located the group around 7:20 a.m. PT Monday, according to the Placer County Sheriff's Office. A rescue crew was inserted into the area and led the hikers out of harm's way, according to the sheriff's office.