SAN DIEGO (CNS) - With increasing summertime heat in the extended local weather forecast, two popular hiking areas in the San Diego-area back country will be off limits to the public for the remainder of August, forestry officials announced Monday.

The San Diego River Gorge and Three Sisters trails will be closed for the next three weeks "to ensure public safety and to preserve personnel and aviation (access) in the event of emerging wildfires," according to a statement from Cleveland National Forest public affairs.

Since the beginning of July, emergency services personnel have performed 11 medical rescues and 18 less urgent assists due to extreme heat in the two areas, forestry officials reported.

The locales are much-visited recreation destinations accessed by the San Diego River Gorge Trail and Three Sisters-Cha'chaany Hamuk Trailhead, respectively. The footpaths are considered "reverse-grade trails," meaning the incline is experienced on the return portion of the hike, and both are challenging to traverse under any circumstances, forestry officials noted.

Under extreme temperatures and above average humidity, some hikers experience the hardest part of the trail during peak temperatures, and after depleting any water brought with them, according to the forest-service statement.

Historically, hundreds of visitors experience heat stress in the two areas each year and require medical attention or helicopter rescues. Each incident relies on the local emergency medical system, putting forestry staffers and personnel with partner agencies at risk of exposure to heat illness and hazards associated with aircraft operations.

"As temperatures decrease in the coming weeks, the forest leadership team will revisit the closures of these areas," the CNF statement asserted. "If the hiking areas are found to be safe, the forest will reopen them to provide the public with access to healthy recreational opportunities (in) their national forest."

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