Heat advisories and extreme heat watches will take effect Wednesday as a prolonged heat wave is expected to bring triple-digit temperatures to inland areas of Southern California.
“Another heat wave is coming this week, peaking Thursday, but remaining well above normal into early next week,” according to the National Weather Service. “There is potential for major or extreme heat concerns for at least the next week.”
Heat advisories will take effect at 10 a.m. Wednesday for the Los Angeles County inland coast and areas including the San Fernando, San Gabriel and Santa Clarita valleys, the Santa Monica Mountains Recreational Area, Calabasas, Agoura Hills and the Antelope Valley foothills.
An extreme heat watch will be in effect from 8 p.m. Wednesday through 8 p.m. Monday.
The heat advisory for the Los Angeles County inland coast, including downtown Los Angeles, will remain in effect through 8 p.m. Monday.
Forecasters said temperatures will increase only slightly Tuesday before climbing more sharply Wednesday. By then, highs are expected to reach the 80s in coastal areas away from the beaches and the 90s to low 100s in the valleys before peaking Thursday.
Highs in the lower mountain elevations and far inland areas are forecast to reach around 100 to 103 degrees, with most locations running about 4 to 8 degrees above seasonal averages.
Thursday is expected to be the hottest day, with temperatures reaching 104 to 107 degrees in the warmest inland areas, according to the NWS.
Overnight temperatures also are expected to remain well above normal in many valleys.
Forecasters said some cooling is possible Friday as the marine layer deepens, but temperatures are expected to rise again over the weekend as the high shifts east.
Forecasters also will monitor the potential for monsoonal moisture and isolated afternoon thunderstorms.
The weather service urged residents to drink plenty of water, seek air-conditioned shelter, avoid prolonged sun exposure and check on relatives and neighbors during the heat.