Record heat has plagued Californians in the East Bay and Los Angeles for a few days now—and San Francisco might finally experience the heat. On Tuesday, the National Weather Service expanded its heat advisory to include the city as well as the Pacific Coastline.
Temperatures in the city are expected to reach into the high 80s Tuesday as a Labor Day weekend “heat dome” continues to trap in hot air and hold the city’s famous marine layer far out to sea. Daytime highs steadily rose over the weekend, and meteorologists predict that Tuesday will show record-high temperatures, exceeding 110 in inland areas of the East Bay and Central Valley.
“We are entering the heart of this heat event,” a spokesperson from the California Public Utilities Commission said at a state press conference Monday. State officials warned that the current heat event will last longer and reach higher temperatures than previously anticipated.
While this heat wave makes for good beach and barbecue weather, it could overtax California’s energy system and cause rolling blackouts. As temperatures rise for prolonged periods of time, Californians tend to use more energy to cool their homes than is available.
The California Independent System Operator (ISO) reported Sunday that energy demand is now “approaching record levels,” warning that the multi-day heat wave will increase in intensity even as the long weekend comes to a close. ISO notes that current energy use has created the “highest likelihood” for energy disruptions this summer.
ISO has continued its Flex Alert over San Francisco and the rest of the state, extending the alert an extra day from its Sept. 2 start date. The Flex Alert asks Californians to reduce energy usage from 4 p.m. to 10 p.m., encouraging locals to lower thermostats and turn off appliances.
Energy-reduction efforts from the first half of the weekend have shown promising results, as ISO officials note that statewide, evening electricity loads have come in at about 1,000 megawatts below expectations, or approximately 2% below forecast.
But, as weather forecasters anticipate that these intense, inland and coastal temperatures will remain at or near record highs into the coming week, current conservation efforts might not be enough.
ISO officials warn that during this phase of the heatwave, energy deficits might reach 2,000 to 4,000 megawatts, representing an additional 10% of the state’s total energy demand. In the event that energy demand far outstrips supply, Californians will experience rolling blackouts or rotating outages later in the day.
“We need two to three times as much conservation as we have been experiencing to keep the power on with these historically high temperatures and energy demand,” said a spokesperson from the California Governor’s Office of Emergency Services.
Asked if the utility expected rolling blackouts in San Francisco this weekend, a spokesperson for Pacific Gas & Electric (PG&E) declined to comment, citing a lack of staff on the holiday weekend.
As high temperatures cause concern for energy department officials, health experts encourage Californians to reschedule outdoor events or activities that might increase risk of heat-related illnesses.
“Think of your body as having a thermostat. If you’re alone, and you don’t have air conditioning and heat is increasing, you’ll have to find ways to cool your body down,” said Dr. Tomás Aragón, director of the California Department of Public Health.
“We have a few more days, and it’s going to be tough,” Aragón said. “Be cool. Be hydrated. Be connected, and be informed.”