Temperatures across interior Southern California will climb dramatically as a prolonged heat wave begins Wednesday and could persist into next week.

Starting Wednesday, temperatures are expected to be in the high 90s and low 100s in inland areas. Officials say now is the time to prepare.

A heat wave hitting the West, sending temperatures soaring past the century mark, is expected to persist into the weekend, with the most intense and prolonged heat expected in the Desert Southwest.

The report, released this week, found that 58% of fast-food workers surveyed in July said they had worked in excessive heat conditions in the last year. And nearly half, or 48%, reported experiencing heat illness symptoms including headaches, fatigue, dizziness, confusion, muscle pain or nausea.

A heat wave is supposed to hit Southern California this week, coupled with gusty winds. LA officials say they're prepared for the increased fire risk. The greatest risk areas are in the San Fernando Valley.

A heat wave spreading triple-digit temperatures across Southern California is also raising concerns among fire officials. Carlos Herrera reports for the KTLA 5 Morning News on Aug. 20, 2025.