California fires threaten towns as high winds loom to fan blazes

The fast-moving Caldor Fire swelled to 6,500 acres (2,600 hectares) on Tuesday in the hills east of Sacramento. PHOTO: CALIFORNIA OES/TWITTER

SACRAMENTO (BLOOMBERG) - Wildfires in drought-stricken California threatened towns, severely injured two people and forced the evacuation of 17,000 residents on Tuesday (Aug 17), with the state bracing for an early-season wind storm that could send flames raging out of control.

The fast-moving Caldor Fire, which swelled to 6,500 acres (2,600 hectares) on Tuesday in the hills east of Sacramento, was blazing with zero containment and injured two people who had to be air-lifted to medical facilities, according to the California Department of Forestry and Fire Protection, or Cal Fire. The department didn't describe the nature of their injuries.

California is struggling through one of its worst fire seasons on record, and conditions could deteriorate further in coming days.

Strong, dry winds were expected to hit the northern half of the state late Tuesday, prompting utility PG&E Corp to plan for power cuts to about 48,000 homes and businesses to prevent its electrical lines from sparking more blazes. The company said it expected to begin blacking out customers early Tuesday evening, before the winds struck.

"Everything is just ready to burn," said Emily Heller, a meteorologist with the National Weather Service in Sacramento. Low humidity and winds gusting as high as 35 miles (56km) per hour will create dangerous conditions through late Wednesday, she said.

Such wind storms more typically arrive in September and October, not August. "We have a trough passing to the northeast and when that happens we get northerly winds, which tend to dry out portions of our area even more," Heller said.

On Monday, California broke a milestone of 1 million acres burned, the earliest it has reached that mark in history. Crews are battling 11 large blazes, including the Dixie Fire, the state's second-largest in history. It had grown to 604,511 acres as of early Tuesday on its way to destroying at least 1,180 structures, according to Cal Fire.

Across the Golden State, 6,540 fires this year have torched at least 1,857 structures. No deaths were reported through Monday.

Temperatures will linger in the 90s Fahrenheit through the rest of the week in the Sacramento area, Heller said. In addition to dangerous conditions in California, red-flag fire warnings are also posted across parts of Oregon, Nevada, Utah, Montana, Wyoming, Nebraska and the Dakotas. Air quality alerts due to smoke pollution have spread across the West including through California's Central Valley and covering almost all of Idaho and Montana.

The Caldor fire, which started on Saturday, was threatening the towns of Grizzly Flats and Pollock Pines. It's a "rapidly developing incident because of the shifting winds, dry fuel and humidity levels around 10 per cent," said Chris Vestal, a spokesman for the Sacramento Metropolitan Fire District.

As drastic as California's fire season has been so far, it is still weeks away from its peak, when the Santa Ana and Diablo winds start to blow from the east.

As the weather patterns of summer give way to fall, large high-pressure systems typically build over the Great Basin of Nevada and Utah, sending winds rushing from the east to low-pressure systems that often develop off the Pacific coast.

These winds dry out and heat up as they cross California's mountain ranges, allowing them to fan any sparks they catch into major fires. Four of the state's five most destructive fires occurred in October and November.

The danger often doesn't pass until winter's rain and snow squelch the flames. But the possibility of another La Nina event this fall and winter, the second in as many years, could bring California another dry winter.

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