Heat Advisory Extended Through Monday Evening for Southern California Valleys and Mountains
The National Weather Service has extended the heat advisory for Southern California valleys and mountains through 8 p.m. Monday, August 24, 2026.
4 reports on this incident · first at Aug 21, 2026, 3:31 p.m. ET
Earlier reports
Aug 21, 2026, 3:53 p.m. ET
Heat Advisory for San Bernardino and Riverside County Valleys, Inland Empire, and San Diego County Valleys Through Monday
The National Weather Service in San Diego has issued a Heat Advisory for several areas in Southern California, effective from 10 AM Saturday, August 22, to 8 PM PDT Monday, August 24. The advisory covers Orange County Inland Areas, Riverside County Mountains, San Bernardino and Riverside County Valleys-The Inland Empire, San Diego County Mountains, San Diego County Valleys, and Santa Ana Mountains and Foothills.
Temperatures are expected to reach 90 to 97 degrees in Inland Orange County, 90 to 102 in inland San Diego County, 98 to 106 in the Inland Empire, and 89 to 99 in the mountains. The advisory warns that hot temperatures may cause heat illnesses.
Officials advise drinking plenty of fluids, staying in an air-conditioned room, staying out of the sun, and checking up on relatives and neighbors.
Aug 21, 2026, 3:37 p.m. ET
Heat Advisory for Southern California Valleys and Mountains Starts Saturday
The National Weather Service in San Diego has issued a Heat Advisory warning that hot temperatures may cause heat illnesses. The advisory will be in effect from 10 AM Saturday, August 22, to 8 PM PDT Monday, August 24, 2026.
The advisory covers Orange County Inland Areas, Riverside County Mountains, San Bernardino and Riverside County Valleys-The Inland Empire, San Diego County Mountains, San Diego County Valleys, and Santa Ana Mountains and Foothills. Temperatures are expected to reach 90 to 97 degrees in Inland Orange County, 90 to 102 in inland San Diego County, 98 to 106 in the Inland Empire, and 89 to 99 in the mountains.
The Weather Service advises drinking plenty of fluids, staying in an air-conditioned room, staying out of the sun, and checking on relatives and neighbors.
Aug 21, 2026, 3:31 p.m. ETFirst report
Heat Advisory for San Bernardino and Riverside County Valleys, Inland Empire, and San Diego County Valleys Through Monday
The National Weather Service in San Diego has issued a heat advisory for parts of Southern California, in effect from 10 a.m. Saturday, August 22, to 8 p.m. PDT Monday, August 24. The advisory covers eight zones, including San Bernardino and Riverside County Valleys, The Inland Empire, San Diego County Valleys, and Orange County Inland Areas.
Temperatures are forecast to range from 90 to 97 degrees in inland Orange County, 90 to 102 in inland San Diego County, 98 to 106 in the Inland Empire, and 89 to 99 in the mountains. The advisory warns that hot temperatures may cause heat illnesses and recommends drinking plenty of fluids, staying in an air-conditioned room, staying out of the sun, and checking on relatives and neighbors.
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- Version 121 Aug 2026, 19:56current
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- Version 121 Aug 2026, 19:37current
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- Version 121 Aug 2026, 19:31current
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- Version 121 Aug 2026, 19:53current
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