LOS ANGELES (CBS) — The calendar may say it’s the second day of fall, but Southern California is in for high temperatures and fire danger over the next few days.

A heat warning is in effect for much of the Southland, as temperatures are expected to be in the 90s Friday. They will continue to rise throughout the weekend, and likely peak Monday, when the offshore flow will be the strongest. Triple-digit heat is expected in some areas, such as the Antelope Valley.

Fire danger will remain high due to low humidity levels.

The late-season high-pressure system is expected to weaken next week, which will result in a gradual cooling trend.

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