An excessive heat warning for San Diego-area desert communities will continue through Sunday night.
The warning kicked in at 10 a.m. Thursday and will stretch through 8 p.m. Sunday. Triple-digit daytime highs -- possibly up to 115 degrees -- will prevail in Borrego Springs and other parts of the county's arid eastern reaches, according to the National Weather Service.
The swelter will "significantly increase the potential for heat-related illnesses, particularly for those working (outside) or participating in outdoor activities," the NWS cautioned.
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Authorities advise those braving the torrid conditions to drink plenty of non-alcoholic fluids, wear lightweight and loose-fitting clothing, limit strenuous activities to early morning or evening, take shelter in shady areas or air-conditioned rooms when possible, check up on potentially heat-sensitive relatives and neighbors, and make sure to never leave young children or pets unattended in parked vehicles.
"High pressure aloft will bring heating for inland areas through Saturday with high temperatures 10 to 15 degrees above average," according to the NWS.
"The marine layer and weak coastal eddy will keep coastal areas cooler with night and morning low clouds and fog."
Today's expected temperatures:
- Coast: clouds to sun – mid-70s
- Inland: sunny – mid-80s to low 90s
- Mountains: sunny – near 90
- Deserts: sunny – near 110-115