SAN DIEGO - The summer heat wave that has kept the region toasty and upped the risk of wildfire could soon see an end as increased moisture brings the possibility of rain and temperatures lower toward average Friday through the weekend.
A National Weather Service Red Flag warning for the mountains and deserts will expire at 9 p.m. The alert indicates potential "extreme fire behavior," due to winds of 15 to 25 mph with gusts to 35 mph, low humidity and an abundance of dry vegetation.
"The gradual recovery of humidities for the mountains and deserts that began Thursday afternoon and evening will continue through the weekend with continuing gusty southwest to west winds each afternoon and evening. This will continue near critical fire weather conditions today," according to the weather service.
Forecasters said temperatures would be slightly cooler Friday and the downward trend would continue through the weekend.
High temperatures Friday afternoon are expected to range from 73 to 78 degrees along the coast, 79 to 84 inland, 82 to 87 in the western valleys, 89 to 94 near the foothills, 86 to 92 in the mountains and 103 to 108 in the deserts.
Forecasters said there would be a slight chance of afternoon showers and thunderstorms in the mountains, and any storms that develop could potentially bring localized flash flooding, small hail and lighting.
"Residual mid-level monsoonal moisture will maintain a slight chance of afternoon and early evening thunderstorms, mainly near the mountains, for the next few days," according to the weather service.
At the beaches, a long-period swell will continue to cause big waves and strong rip currents as it peaks today and Saturday.
A beach hazards statement warning of surf of 3 to 5 feet with sets to 6 feet, and rip and longshore currents, which could potentially pull swimmers out to sea, will remain in effect through Sunday.