Marin temperatures break records as heat engulfs region
As temperatures eclipsed 100 degrees in parts of Marin on Tuesday, weather forecasters said this week’s heat wave could linger longer than expected.
The National Weather Service extended an excessive heat warning, which took effect Monday, another day to 11 p.m. July 9, forecasters said.
“Nothing is pushing this high pressure,” meteorologist Nicole Sarment said. “It’s just staying stagnant and showing no signs of breaking down anytime soon. So this is going to be going on a while, maybe longer than we thought.”
Unofficial high temperatures on Tuesday included Novato at 107 degrees; Mill Valley, 96 degrees; Tiburon, 90 degrees; Larkspur, 94 degrees; and Mount Tamalpais, 97 degrees, according to the weather service. The coast remained cooler, with 62 degrees recorded in Point Reyes Station.
San Rafael and Kentfield set records at 103 degrees. The previous highs of 101 were recorded on July 2, 1991.
The Marin County Health and Human Services Department had no immediate plans to open cooling centers or provide emergency shelter for homeless residents. Updates will be posted at marinhhs.org/emergency-information, a county official said.
“The weather forecast is ever changing, so at this point, there are no plans for Marin HHS to open a center as the criteria has not been met,” Laine Hendricks, a county spokeswoman, said in an email. “If that changes, that website will be updated and a formal announcement will be made.”
The criteria to open a shelter include hazardous air quality exceeding an index of 300, according to the county’s website.
A “red flag” warning for severe fire conditions, issued by federal forecasters on Monday, was extended through 5 p.m. Friday in the North Bay. Wind gusts are expected to be at least 25 mph and will combine with relative humidity below 10% and heavy grasses to make for dangerous conditions.
In addition to the heat, minor flooding from tide anomalies could be an issue for some areas of coastal Marin, Sarment said.
Pacific Gas & Electric Co. said it started shutting off power in parts of the region, including Napa, Solano and Lake counties. Other areas affected included Yolo, Colusa, Shasta, Glenn and Tehama counties, in an effort to relieve some pressure on the state’s power grid.
The length of time it takes for power to be restored after an outage will vary, depending on conditions, said Teresa Alvarado, a PG&E executive. Equipment that fails in the heat, causing unplanned outages, may also need attention.
“We have crews that are staged and ready even though it’s a holiday week,” Alvarado said. “We know that it’s essential to get people back in power as quickly and safely as possible.”
The heat is creating smoggy conditions that could make it hard to breathe for small children, seniors and those with heart and respiratory conditions. The Bay Area Air Quality Management District issued its third “spare the air” alert of the year on Tuesday and said it would be monitoring conditions the rest of the week.
The blast of heat — already forecast to be the longest and hottest stretch for the region since the days surrounding Labor Day in 2022 — was expected to jump 10 to 12 degrees from the previous 24 hours in the hottest places on Tuesday and could jump two or three more degrees from there on Wednesday, according to forecasters.
Experts, such as NWS meteorologist Roger Gass, sounded the alarm about its intensity, calling it “extreme.”
Dr. Michael Schmeltz, a college professor of public health at Cal State East Bay, said the overall health of the public “and especially that of children is very vulnerable.”
“This is the first major (heat wave) of the season, and the first major one in a long time. It’s going to catch people off guard,” Schmeltz said. “It’s the week of a holiday. It’s going to put them outside. They’ll be out there with their families, which adds to everyone’s risk in the extreme heat. Kids can be out in it for a long time, and we forget because they’re so little and their bodies are so resilient.
“You can just be standing in the heat, and your breathing rate and heart rate are going to go up,” Schmeltz said. “Adding to that with extra strenuous activity is only going to add to your risk.”
Jan Null, a Bay Area meteorologist for almost five decades, warned anyone out with loved ones or pets in the car that in heat like this, there is no safe time to stop without life-threatening danger.
“(After an hour), the dashboard in that car is gonna be up to 150 degrees,” he said. “Think what that can do. Please put something in the backseat of your car, a wallet or purse, so that you don’t forget somebody is back there. It’s not a slow bake.”
Although temperatures will cool down some during the evening, but the overnight lows will remain higher than average during the heat wave. That means that temperatures at sunrise will already be significantly warm, forecasters said.
IJ reporters Giuseppe Ricapito and Krissy Waite, and Bay Area News Group reporters Rick Hurd, Caelyn Pender, Martha Ross and Jason Green, contributed to this report.