SAN DIEGO - A red flag warning signifying wildfire conditions remained in effect Friday in the mountains and inland valleys of San Diego County amid hot, dry conditions and gusty winds.
During the warning period, set to expire at 6 p.m., east-to-northeast winds of 15 to 25 miles per hour with gusts as strong as 45 mph are expected as the humidity level drops to about 5 percent, according to the National Weather Service.
Temperatures in the valleys are forecast to range from 90 to 98 degrees, in the 70s and 80s in mountain areas with altitudes of between 3,000 and 6,000 feet and in the upper 60s in higher areas.
"A combination of strong winds, low relative humidity and warm temperatures will create explosive fire growth potential," according to an NWS advisory.
Marine air is expected to begin heading north along the coast late tonight, bringing fog, forecasters said.
A dense fog advisory is scheduled to take effect at 11 p.m. in coastal areas from Imperial Beach to San Onofre, west of Interstate 5, where visibility could be reduced to less than a quarter-mile. It will expire at 11 a.m. Saturday.
Cooler weather and higher humidity levels are expected this weekend, forecasters said.
The possibility of rain and thunderstorms will follow from Sunday night into Monday, according to the weather service.