A Red Flag Warning was issued for portions of Napa County this weekend, with Pacific Gas & Electric saying it might proactively turn off the power in some areas.
High winds are expected beginning Friday evening through Sunday afternoon, with the highest threat in the hills of eastern Napa County and near Mount St. Helena, the National Weather Service said Friday.
PG&E said late Friday afternoon that it had reached out to 1,600 customers on both sides of Lake Berryessa to let them know that power could be shut off as early as 6 a.m. Customers can visit pge.com/eventmap to see whether their neighborhood may be impacted.
Elevations above 1,000 feet can expect strong northeast winds between 15-25 mph, gusting from 40-50 mph, with relative humidity values dropping Saturday into the lower teens, the Weather Service said.
PG&E said it would be monitoring the fire danger and might turn off the power as a safety measure for portions of Napa County and the Lake Berryessa area.
“We know how much our customers rely on electric service and would only consider temporarily turning off power in the interest of safety during extreme weather conditions,” said Michael Lewis, PG&E’s senior vice president of Electric Operations.
PG&E put its customers on notice this spring that it would turn off the power when high winds threatened transmission lines. Downed lines have sparked major wildfires over the past two fire seasons.
In the North Bay, there is the potential for a Public Safety Power Shutoff affecting several thousand customers starting around 6 a.m. Saturday, the utility said in a news release. The peak period of fire risk lasts until around 1 p.m. on Saturday, PG&E said.
Deanna Contreras, a PG&E spokesperson, said local government was being notified of the possible power shutoffs and customers most at risk would be getting text messages, emails or phone calls later Friday.
Other nearby areas where electricity might be shut off proactively include Vacaville, Suisun City, Davis and Winters.
The Weather Service said the Bay Area could expect “autumn-like offshore winds” with temperatures rising close to triple digits on Sunday.
Napa’s high on Saturday will be 90 degrees, rising into the upper 90s Sunday and Monday, prompting the Weather Service to issue a Heat Advisory.
Although wildland fuels are not at critical dry levels, a weather event of this magnitude will allow fire to carry through finer fuels such as grass, the Weather Service said.
Napa County Public Health Officer Karen Relucio said in a press release sent late Friday afternoon that people particularly susceptible to heat exhaustion include seniors, people who work or exercise outdoors, infants and children, and people with chronic medical conditions.
People should seek medical help if they experience profuse sweating and cramping, hot and dry skin, a body temperature of 105 degrees, and confusion or unconsciousness.
Heat stress can be observed in pets who are panting heavily, have glazed eyes, have a rapid pulse, are unsteady or have a staggering gait, are vomiting, and have a purple or dark red tongue.