More thunderstorms were possible Monday for the mountains and deserts thanks to monsoonal flow that was also creating a thick marine layer along the coast in the morning, forecasters said.
A few showers and thunderstorms rolled across San Diego County over the weekend with Barona recording 0.04 inches of rain, and Alpine and Ramona recording 0.01 inches, the National Weather Service said.
It's possible the mountains and deserts could see additional showers and thunderstorms on Monday.
Record low temperatures were also set in those same areas, the National Weather Service said. Overnight lows were 68 in Ramona and 91 in Borrego, which last set record lows in 2006 and 2009 respectively.
Strong high pressure over the Southwest was predicted to bring hot summer weather inland while sea breezes and a shallow marine layer could keep coastal areas much cooler.
Hot, dry weather returns Tuesday through Friday, followed by cooling next weekend as the upper high over the Southwest weakens.
An excessive heat warning was issued until 8 p.m. Sunday for San Diego County deserts, including Borrego Springs, with dangerously hot conditions and temperatures reaching 114 degrees.