Strong Santa Ana winds and low humidity will significantly raise the threat of wildfires Wednesday in San Diego County, according to the National Weather Service.
The NWS issued a red flag warning that will be in effect until 6 p.m. Thursday in the county mountains and valleys.
The threat was deemed high, according to the Sana Ana Wildfire Threat Index, which means that "upon ignition, fires will grow very rapidly, will burn intensely, and will be very difficult to control."
San Diego Gas & Electric officials said the utility was considering precautionary power shutoffs for more than 40,000 customers. The shutoffs would be implemented to de-energize power lines in danger of being damaged or downed by strong winds, potentially sparking wildfires.
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As of 2:15 p.m., SDG&E had shut off power to 25,500 homes and businesses in Alpine, Boulevard, Campo, Descanso, Dulzura, portions of El Cajon, portions of Encinitas, portions of Escondido, Fallbrook, portions of Jamul, Julian, Mount Laguna, Pala, Pauma Valley, Pine Valley, Potrero, Poway, Rainbow, Ramona, portions of Rancho Bernardo, portions of Rancho Santa Fe, an unincorporated area east of San Juan Capistrano, Santa Ysabel and Valley Center.
An additional 15,369 addresses faced potential precautionary power-downs in Jacumba, portions of Lakeside, Palomar Mountain, Ranchita, and unincorporated areas east of San Clemente, portions of San Marcos and Warner Springs.
If power is shut off for an extended period of time, SDG&E may open community resource centers where residents can get water and snacks, charge their phones and get up-to-date information about the outages.
A full list of the center locations can be found at: www.https://www.sdge.com/wildfire-safety/public-safety-power-shutoffs.
The San Diego County Office of Education announced that schools in the Dehesa School District, Mountain Empire Unified School District, Rancho Santa Fe School District, Spencer Valley School District, Warner Unified School District and all schools in Julian will be closed Wednesday because of the power shutoffs.
Conway Elementary and Del Lago Academy in Escondido, along with Double Peak Elementary, San Elijo Elementary and San Elijo Middle School in San Marcos will also be closed Wednesday in anticipation of power shutoffs, said Music Watson, a spokeswoman with the county Office of Education.
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Winds out of the east and northeast are expected to be between 25-35 mph, with gusts reaching 55 mph in the valleys and 75 mph near mountain ridge tops, forecasters said. Relative humidity will drop as low as 5%, with poor overnight recovery expected through Friday.
The winds will increase Wednesday morning and become more widespread after sunrise, then wind speeds will decrease Wednesday evening through Thursday morning, according to the NWS.
A high wind warning will also be in effect until 6 p.m. Thursday in the county mountains and valleys. Officials warned that damaging winds could blow down trees and power lines, while travel will be especially difficult for high-profile vehicles.
Temperatures Wednesday could reach 77 degrees near the coast and inland, 78 in the western valleys, 69 near the foothills 60 in the mountains and 71 in the deserts.
