The National Weather Service issued a heat advisory for much of Southern California, including Los Angeles and Orange counties.
The advisory is in effect from 10 a.m. Wednesday to 8 p.m. Thursday. Meteorologists expect temperatures to reach anywhere between 85 and 105 degrees, roughly 10 to 20 degrees above normal.
NWS said temperatures will peak on Wednesday in most areas and that humid conditions will make the heat feel even more uncomfortable.
The LA County Department of Public Health urged residents to stay hydrated, keep their homes cool and never leave children or pets in a car, even if the window is cracked.
A map showing the areas under the heat advisory.
Public health staff recommended that residents without air conditioning visit a library, cooling center or anywhere with air conditioning.
To find a location near you, visit https://ready.lacounty.gov/heat/ or call 211.
Symptoms for heat-related illnesses vary, but common signs include heavy sweating, cramps, dizziness and confusion. LA County Public Health provided a full list of symptoms here.
"Heat causes more deaths in the U.S. annually than floods, storms, and lightning combined. Those most likely to get ill during the heat include older adults, young children, outdoor workers, athletes, and individuals with chronic medical conditions," said Dr. Muntu Davis, LA County Health Officer.
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