An excessive heat warning has been issued for parts of San Diego County from 10 a.m. Friday until 8 p.m. Sunday, according to the National Weather Service.
Dangerously hot conditions are expected in Borrego Springs and the San Diego deserts with temperatures up to 116.
Other parts of San Diego County can also expect hot temperatures but were not under any heat advisories or watches as of Friday morning.
Extreme heat can increase the potential for heat-related illness, particularly for those working or participating in outdoor activities. The NWS recommends drinking plenty of fluids, staying in air-conditioned rooms and out of the sun, and checking on relatives and neighbors.
Young children and pets should not be left unattended in vehicles.
On top of warm weather, it's possible the deserts and mountains could see some thunderstorm activity Friday afternoon. With it could come gusty winds, brief heavy rain and small hail, the NWS said.