A week of record-breaking temperatures includes a red flag fire weather warning for part of Los Angeles County, historically one of the most dangerous times of the year for wildfires.

Temperatures are expected to cool slightly this weekend, but not before above-average heat, which warranted excessive heat warnings and advisories until at least Thursday 8 p.m. Some areas in the Santa Clarita and San Fernando valleys are expected to reach well into the triple digits on Thursday.

A red flag warning is in effect for the western San Gabriel Mountains and the 5 and 14 freeway corridors until 8 p.m. Thursday. The warning extends into the mountains of LA and Ventura County.

The acute fire danger warning was issued due to heat, gusty north-easterly winds and low humidity.

“There is a high risk of fires growing and unfortunately spreading,” said NBC4 forecaster Belen De Leon. “A lot of it has to do with these temperatures. We are well above normal.”

The warning comes as three major wildfires that started nearly a month ago continue to burn in several Southern California counties. The most active fire, the Line Fire in San Bernardino County, was 79 percent contained at 43,900 acres. Some evacuations remain in place.

Cal Fire statistics updated Tuesday show 6,528 wildfires have burned 1,001,993 acres so far this year. Last year, in early October, 5,492 wildfires burned 293,462 acres.

Total acreage brings California close to its five-year average as of early October of 1,085,577 acres.

The community of Big Bear Lake, including Moonridge, Sugarloaf and South Erwin Lake, was under an evacuation warning Tuesday. Christian Cázares reports for NBC4 News on Tuesday, October 1, 2024 at 3 p.m.

Fall is typically the worst time of year for wildfires in Southern California due to dry conditions and the notorious Santa Ana winds, which have fueled some of the region's most devastating fires.

Temperatures will cool down a bit on Thursday evening and will be even cooler on Friday. In areas far from the coast, maximum temperatures are still 5 to 10 degrees above normal.

Some areas will likely fall under excessive heat warnings or warnings again this weekend, with only slight cooling.

Significantly cooler weather is expected until Tuesday.

Southern California Temperature Records

Some communities broke record high temperatures on Wednesday.

• Woodland Hills reached 111, breaking the daily record of 109 set in 1991.
• Palmdale Airport peaked at 105, breaking the daily record of 101 set in 2020.
• At Lancaster Fox Field there were 104, breaking the single-day record of 101 set in 2012.