San Diego Gas & Electric has notified 83,609 customers that they could lose power Monday and Tuesday when parts of San Diego County are hit by the third beastly Santa Ana windstorm to imperil Southern California this month. The notices went out Saturday as the National Weather Service was telling the public that a red flag fire weather warning will be in effect from 8 a.m. Monday to 10 p.m. Tuesday for areas generally east of Interstate 15. Forecasters say the winds could reach 70 mph along Interstate 8 east of Alpine, making driving difficult along one of the most important traffic corridors in the region. Winds could gust to 95 mph at Sill Hill in the Cuyamaca Mountains. The winds will arrive from the east, giving them a clear path into the county’s mountains and foothills, which are experiencing unprecedented dryness, forecasters said. Wildfires that erupt in that area often spread west toward heavily populated communities, sometimes leading to widespread evacuations. The relative humidity late Monday and Tuesday will drop as low as 6%, which makes dry vegetation even more flammable. And extremely cold air from Canada will arrive in the region at the same time. Many people who lose power could end up without heat for one to two days. “This looks like a very serious event,” said Brian D’Agostino, vice president of wildfire and climate science at SDG&E. “We’ll have wind chills way below freezing in the higher terrain of the county — air temperatures close to 30 degrees, with strong winds, creating dangerous wind chills,” he said. The utility periodically shuts off power before windstorms to reduce the chance that its power lines and other equipment will spark a wildfire. This is done through a program known as Public Safety Power Shutoff. The newly issued notices went to many communities in the eastern and northern areas of the county, including Alpine, Barona Reservation, Borrego Springs, Campo, Descanso, Valley Center, El Cajon, Escondido, Fallbrook, Julian, Lakeside, La Posta Reservation, Poway and Ramona, among others. The notices also were sent to some areas of San Diego, including Carmel Valley and Del Mar. Wildfires are always a source of concern, especially in the wake of the fires that recently devastated parts of Los Angeles County. “Recent fires have shown high resistance to control, with rapid spread and frequent spotting, with retardant often proving ineffective in the control of the fire environment,” the Southern California Geographic Area Coordinator said in a statement.