Weather helping firefighters battle massive Mountain blaze

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A plume of smoke looms over Lake Hemet as a water-dropping helicopter heads to the lake to refill. (Gina Ferazzi / Los Angeles Times)

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Frank Boimilla, left, and Nathan Saucedo of Lake Elsinore fish on the edge of Lake Hemet as the Mountain fire burns in the background above Highway 74. (Gina Ferazzi / Los Angeles Times)

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Residents of Idyllwild stand in the center of town and watch a towering plume of smoke rise from the Mountain fire that’s burning in a wilderness area a few miles north of the community. (Don Bartletti / Los Angeles Times)

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U.S. Forest Service firefighters water down the smoldering embers of a mobile home on Bonita Vista Road in Mountain Center. (Don Bartletti / Los Angeles Times)

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Kern County firefighters take a break on the shores of Lake Hemet as a water-dropping helicopter refills during the Mountain fire off Highway 74. (Gina Ferazzi / Los Angeles Times)

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Orange hazy smoke fills the air above Lake Hemet as a water-dropping helicopter uses the lake to refill during the Mountain fire off Highway 74 at Mt. San Jacinto State Park. (Gina Ferazzi / Los Angeles Times)

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A firefighting C-130 aircraft is dwarfed by a plume of smoke from the Mountain fire near Idyllwild. The wildfire had scorched more that 22,800 acres by Thursday afternoon and was only 15% contained. Evacuation of more than 2,000 homes was ordered around Idyllwild. (Luis Sinco / Los Angeles Times)

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San Bernardino County firefighters walk through scorched terrain as they look for hot spots and fire-damaged trees around Idyllwild. (Luis Sinco / Los Angeles Times)

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A police cruiser speeds past a line of mailboxes along Highway 74 in Hemet as the Mountain fire rages in the distance. (Luis Sinco / Los Angeles Times)

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The Mountain fire burns out of control, forcing evacuations off Highway 74. (Gina Ferazzi / Los Angeles Times)

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Charred remains of motor bikes stand at a residence on Bonita Vista Road. (Irfan Khan / Los Angeles Times)

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A photographer shoots the Mountain fire on the hills along Apple Canyon Road in Mountain Center. (Irfan Khan / Los Angeles Times)

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Lon Paul, a well-known gunmaker, lost his shop to the wildfire that ravaged through his place on Bonita Vista Road in Mountain Center. (Irfan Khan / Los Angeles Times)

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The Mountain fire looms in the background of Morris Ranch Road off Highway 74 in Garner Valley on July 17. Authorities ordered more evacutations in the area. (Gina Ferazzi / Los Angeles Times)

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Arrowhead Hotshots from Kings Canyon National Park march down Mountain Fire Base Camp set up along Highway 74 in Mountain Center. (Irfan Khan / Los Angeles Times)

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Firefighters prepare hoses at Mountain Fire Base Camp set up along Highway 74 in Mountain Center. (Irfan Khan / Los Angeles Times)

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Fire retardant is dropped on a hillside near a church campground in Mountain Center. Mandatory evacuations were ordered for 24 homes in the Bonita Vista and Fleming Ranch communities. Evacuation centers for residents and pets were set up at local schools and animal shelters. (Irfan Khan / Los Angeles Times)

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A burned-out vehicle sits at a residence on Bonita Vista Road. (Irfan Khan / Los Angeles Times)

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Barbara Lundquist, 71, was evacuated from Idyllwild and spent the night in her 1969 VW van parked near Lake Hemet. Evacuation orders affecting about 6,000 people remained in force Thursday as the Mountain fire near Idyllwild and Fern Valley continued to burn. (Irfan Khan / Los Angeles Times)

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Art Jaenke of Garner Valley hoses down a large shed on his property to prepare as the Mountain fire looms in the background. Jaenke is staying behind to protect his property, despite calls to evacuate. (Gina Ferazzi / Los Angeles Times)

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Irene Jaenke of Garner Valley prepares to evacuate with her pets as the Mountain fire looms in the background in Garney Valley. (Gina Ferazzi / Los Angeles Times)

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Resident Art Jaenke of Garner Valley, middle, watches the approaching Mountain fire with U.S. Forest Service firefighters Matt Boss, left, and Josh Richardson, near Highway 74 on July 17. Residents were told to evacuate, but Jaenke stayed behind to protect his property. (Gina Ferazzi / Los Angeles Times)

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A firefighter walks past a burned structure at a church campground on top of Apple Canyon Road in Mountain Center. (Irfan Khan / Los Angeles Times)

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Firefighters respond to a burned structure at a church campground located on top of Apple Canyon Road in Mountain Center. (Irfan Khan / Los Angeles Times)

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A town hall located at a church campground suffered some fire damage to its steps in Mountain Center. (Irfan Khan / Los Angeles Times)

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A hillside can be seen burning from the church campground. (Irfan Khan / Los Angeles Times)

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A hillside burns in Mountain Center. (Irfan Khan / Los Angeles Times)

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A fire crew returns from protecting Zen Mountain Center at the top of Apple Canyon Road in Mountain Center. (Irfan Khan / Los Angeles Times)

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A helicopter drops water on the brush along Apple Canyon Road in Mountain Center. (Irfan Khan / Los Angeles Times)

By Rong-Gong Lin II

July 21, 2013 8:49 AM PT

The massive Mountain fire burning above Palm Springs is now nearly 50% contained.

But officials said the fire remains a danger, and several mountain towns including Idyllwild remain under mandatory evacuation orders.

Crews were helped by the arrival of monsoonal moisture from the Gulf of Mexico, lowering temperatures, increasing the humidity and bringing light rain.

Officials remained on guard, however, in case the weather system brings lightning strikes, or heavy rain that could cause flash flooding.

The Mountain fire, which began last Monday, has destroyed or damaged more than a dozen structures including some homes in the Bonita Vista and Pine Springs areas.

The Mountain fire has burned through 27,000 acres. A portion of the fire is near the Palm Springs Aerial Tramway, and half a dozen crews were defending that area.

To the west, firefighters have a better handle on the 700-acre Rancho fire near the Grapevine, which forced the brief closure of Interstate 5 on Friday. No structures have been damaged in that blaze but evacuations near the Lebec town center remain in effect.

Crews have 85% of that blaze surrounded.

Humid conditions were expected to last in Southern California through Monday.

Light rain in the Los Angeles Basin and Orange County was expected to bring precipitation of 0.15 inches.

Most places won’t see enough rain to scratch summer picnic plans, but a handful of areas could see a stray thunderstorm that could dump as much as half an inch of rain, “and there’s no way we can pinpoint where that is,” said Miguel Miller, a National Weather Service forecaster in San Diego.

“I wouldn’t cancel plans,” Miller said, “but it’s something to certainly be aware of. If you’re out somewhere, you might need to pick up quickly.”

The increased humidity and cloud cover have brought temperatures down into the 70s in the L.A. Basin and 80s in the valleys.

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