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.

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.

Los Angeles — A dangerous heat wave descended on much of California and the U.S. Southwest, with triple-digit temperatures expected along with a higher risk of wildfires.

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.

The buildup is over; Wednesday is the day that triple-digit temperatures and dangerous fire conditions spread across much of Southern California. KTLA's Vera Jimenez and Kimberly Cheng report on Aug.