A California utility shut off power to 12 counties in the northern part of the state as a “dark wind” – notorious for its hot, dry gusts in the fall – increased the risk of wildfires ignited by power lines. About 13,000 customers woke up without power Friday after Pacific Gas and Electric Co. shut off power.
The “Dark Winds” are expected to produce sustained winds of up to 35 mph (56 km/h) in many areas, with mountaintop gusts possibly reaching 65 mph (104 km/h), according to the National Weather Service. Strong winds are expected to continue throughout part of the weekend.
PG&E said the utility began cutting power to customers in 12 counties on Thursday, including Alameda, Contra Costa, Napa, Solano and Sonoma counties in the Bay Area. and some customers further north in Colusa, Glenn, Tehama and Shasta counties. In total, about 20,000 customers may temporarily lose power in the coming days, PG&E said in a statement Thursday.
Forecasters have issued a red flag warning of fire danger through Saturday from the Central Coast through the San Francisco Bay Area and into northern Shasta County, not far from the Oregon border. , said Brayden Murdock, a meteorologist with the weather service’s Bay Area office. “We want to tell people to be careful.”
During the dark winds common in autumn, the air is very dry and the relative humidity drops sharply, causing vegetation to dry out and burn easily. The name – “diablo” is Spanish for “devil” – informally refers to hot winds blowing toward the coast from near the San Francisco area as high pressure builds in the West.
Targeted power outages are also possible in Southern California, where another notorious weather phenomenon – Santa Ana winds – is expected to hit the area on Friday and Saturday.
Santa Anas are dry, warm, and gusty northeasterly winds that blow from inland Southern California toward the coast and offshore, countering normal onshore air currents that bring moist air from the Pacific Ocean into the region. The National Weather Service issued a red flag warning for the valleys and mountains of Los Angeles County, parts of the Inland Empire and the San Bernardino Mountains. Winds around the greater Los Angeles area won’t be as strong as in the north, with gusts of 25 to 40 mph (40 to 64 mph) possible in the mountains and foothills, said Mike Wofford, a meteorologist with the weather service’s Los Angeles field office. km/h) gusts.
He said the strongest winds were recorded in the Santa Monica and San Gabriel mountains, with gusts between 45 and 55 mph (72 and 88 kph) on Friday, with isolated gusts as high as 60 mph (96 kph). /Hour). “The humidity is drying out, and with the wind, if we have a spark, it could really spread quickly because of the conditions we have right now,” Wofford said.
Meanwhile, light snow fell on some mountaintops around Lake Tahoe Friday night, according to the National Weather Service in Reno, Nevada.
Temperatures are expected to be close to below freezing again Friday night into Saturday, the National Weather Service said. Wind sensors on two mountain peaks west of Lake Tahoe recorded wind speeds of 75 mph and 104 mph on Friday, with strong winds expected. It will continue through the night before tapering off Saturday morning.
The department also issued the first ice warning of the season from 2 a.m. to 9 a.m. Friday along the eastern edge of the Sierra Mountains, from south to north of Carson City and into California’s Lassen County, Sierra County, and Sierra Nevada through Reno. La and Plumas counties, where temperatures could drop to the lowest temperatures.
“Frost and freezing conditions can kill crops and other sensitive vegetation and can damage unprotected outdoor pipes,” the department said.