Triple-digit temperatures are possible again Thursday in most of San Diego County, but cooler conditions are expected starting Friday, according to the National Weather Service.
High pressure centered over the Four Corners region will begin moving east on Friday as a trough of low pressure moves over the west coast and brings cooling from Friday through Sunday, forecasters said.
The agency issued an excessive heat warning that will last until 8 p.m. Thursday in the county deserts.
High temperatures Thursday are forecast to reach 83 degrees near the coast, 92 inland, 95 in the western valleys, 102 near the foothills, 100 in the mountains and 117 in the deserts.
The mercury in the deserts is expected to drop to 114 on Friday, forecasters said. Highs in the western valleys are expected to dip into the high-80s to low-90s on Friday, while temperatures near the foothills will drop to the high-90s.
The NWS urged residents to drink plenty of fluids, stay out of the sun and check on relatives and neighbors. Also, children, seniors and pets should be never be left unattended in a vehicle, with car interiors able to “reach lethal temperatures in a matter of minutes,” according to the NWS.
Borrego Springs set a high temperature record for the date on Wednesday, while Campo tied its 2011 high of 104 degrees, according to the NWS. The mercury in Borrego Springs reached 116, besting its 2017 high of 114 for Aug. 26.
To help the public beat the heat, the county is offering nine cooling centers in Alpine, Borrego Springs, Fallbrook, Lakeside, Potrero, Ramona, Santa Ysabel, Spring Valley and Valley Center. Due to the coronavirus, mandatory mask- wearing and social-distancing protocols are enforced in the facilities.
A full list of the cooling center locations can be found at: https://www.sandiegocounty.gov/content/sdc/hhsa/programs/ais/cool_zones.html.