Thursday, November 13, 2008

mood swings

Sheriff's helicopter after sunrise, Rialto, November 2007.
Cucamonga Peak and east San Gabriels in the distance.

By Guy McCarthy

CAJON PASS - Just a few days after a cold front contributed to at least eight deaths in San Bernardino County, the National Weather Service has issued red flag warnings in Southern California for increased fire danger due to near-record heat, low humidity, and a return of Santa Ana winds.

Fire crews are expected to be on heightened alert from tomorrow morning through at least Saturday afternoon. Officials in San Diego issued warnings for the Inland Empire and the Santa Ana Mountains and foothills at 12:55 p.m. today. Warnings for Los Angeles and Ventura counties were issued this morning.

From the San Gorgonio Pass to the San Fernando Valley, local, state and federal agencies are well aware of the potential for critical fire weather.

Forecasters can see the winds coming days in advance - but nobody knows for sure where they'll strike hardest.

"This might be the first serious Santa Ana event of the season," said Bill Patzert, an oceanographer and forecaster for NASA's Jet Propulsion Lab in La Canada Flintridge. "The others so far have been puny.

"The high pressure system over the Great Basin is setting up in the classic position," Patzert said in a phone interview today. "I think we're going to see record or near-record temps up to 100 degrees in the inland valleys, for the next three days.

"These definitely qualify as devil winds," Patzert said. "We haven't seen the meteorology lined up like this in a while. The problem is you never know which canyon or pass is going to get it."

Weather Service forecasters in Oxnard issued red flag warnings before noon today. Their counterparts in San Diego had issued fire weather watches on Tuesday, said NWS meteorologist Steve Vanderburg.

"Typically the worst areas for the winds are in and below the Cajon Pass, and communities like Devore, Rialto, Ontario and Corona," said Vanderburg, who is based in San Diego.

From critical fire weather conditions to cold fronts and back again, the whipsaw mood swings of mother nature are routine this time of year, Vanderburg said.

"This happens in Southern California as fall transitions into winter," Vanderburg said. "We can get stuck in this pattern, with heat waves followed by cold storms. You can see radical temperature swings in the valleys, because you're close to the mountains.

"You have an 11,000-foot range there, and the valleys drop down as low as 500 feet elevation in places," Vanderburg said. "You see a bit of everything."

The cold front that moved across Southern California early Sunday brought high winds that hurled dust and sand across a vast region, from the Owens Valley to the lowlands of Riverside and San Diego counties. It also slammed some mountain areas with sleet, snow and blizzard conditions.

Four died in a plane crash Sunday in the storm-shrouded San Gorgonio Wilderness, just hours after whiteout conditions cut off two Los Angeles-based hikers on 11,500-foot San Gorgonio Mountain. Also Sunday morning, four people died in a multi-vehicle pileup on Interstate 40 east of Barstow that included at least three bigrigs.

"Pilots need to fly within their personal flight restrictions, and people driving need to know when to slow down or pull over," said San Bernardino sheriff's Lt. Dale Gregory, who helps oversee his department's aviation unit at the foot of the Cajon Pass.

Flight crews from the Rialto base responded to several incidents in the mountains in the past few days, including a rescue of the stranded hikers and recovery of those who died in the plane crash on 10,459-foot Dobbs Peak.

Today they're bracing for more heat, winds and fire potential, Gregory said in a phone interview.

"We're staffing a second fire ship, at the request of the state," Gregory said, referring to a military-surplus helicopter equipped with tanks for dropping retardant or water loads.

"This is part of the job," Gregory said. "We have to be ready for whatever nature brings."


Helicopters, one equipped for firefighting.
On standby in Rialto, November 2007.

Photos by Guy McCarthy.

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