SAN DIEGO - The hiking trails to Three Sisters and Cedar Creek Falls were closed Monday due to the heat.
The Cleveland Forest Service made the announcement Monday morning and expected to keep the areas closed until the excessive heat advisory expired.
The two popular East County trails were expected to reopen on Friday, July 27.
San Diego County again will face extreme heat and high surf beginning Monday and lasting through Thursday, the National Weather Service said.
Forecasters said a high-pressure system moving over Southern California will bring in an extended period of hot weather, with the peak of the sweltering conditions to occur Tuesday and Wednesday.
It prompted the NWS to issue an Excessive Heat Warning for San Diego County, along with most of Southern California, between 10 a.m. Monday and 8 p.m. Thursday.
High temperatures are expected to range anywhere from 96 to 98 degrees in Escondido and El Cajon Monday, and Vista was expected to see temperatures as high as 88.
Record temperatures Tuesday and Wednesday could be broken in San Diego, Chula Vista, Escondido, Ramona and Alpine, according to the NWS.
Temperatures near the immediate coast are expected to reach the lows 80s, but not much higher.
The NWS issued a High Surf Advisory beginning Monday at 8 a.m. and lasting through 9 p.m. Wednesday.
Strong rip currents could cause dangerous swimming conditions for inexperienced swimmers, the NWS said.
Surf levels of 6-8 feet will be possible, forecasters said.
The desert northeastern corner of San Diego County will continue to see high temperatures, reaching a climax of 117 degrees on Tuesday.
A list of "cool zones" for residents to escape the heat can be found online.