Heat wave....

'Prolonged, dangerous' heat wave coming to California this week

Amy Graff

California is bracing for a brutal heat wave that's expected to send temperatures soaring, likely to record highs in some locations, over the upcoming three-day Labor Day weekend. Forecasters are saying this event will bring the hottest spell of weather the state has seen so far this year. 

As a result, National Weather Service offices across the state started issuing heat advisories on Tuesday for later in the week warning of "very dangerous" heat. 

"Looking increasingly like a prolonged, dangerous, and almost certainly record-breaking heat event," Daniel Swain, a climate scientist at UCLA, wrote on Twitter. 

The sizzling hot weather comes as a strong ridge of high pressure centered over Nevada builds into California. "It will nudge to the west in the next few days and we'll start to see temperatures start to go up on Thursday," said Alexis Clouser, a forecaster with the weather service's Monterey office. 

Southern California and the Central Valley will see some of the most extreme conditions. In the Sacramento Valley, daytime highs are forecast to range from 100 to 115 degrees, Saturday through Tuesday, the weather service said.

"It's going to be extremely hot," said Katrina Hand, a forecaster with the weather service in Sacramento. "The entire population should plan to practice heat safety by avoiding outdoors activities during the peak heating hours of the afternoon and drinking lots of water."

In SoCal, coastal areas may not get above 100 degrees, but interiors will be sizzling, with the forecast calling for afternoon highs of 95 to 110 degrees through Saturday and up to 115 Sunday and Monday. 

Death Valley could hit a scorching high of 124 on Saturday and Sunday, and then inch down to 121 on Monday.

"This heat may be record breaking and will produce a very high risk of heat illness," the weather service's Los Angeles office said.

The San Francisco Bay Area will experience some of the coolest temperatures in the state, but the inland areas will still bake with triple-digit heat and the weather service is warning of dangerous conditions. In inland areas, temperatures will soar into the 100s at least three days in a row, Saturday through Monday, while coastal spots will get into the high 80s to low 90s, the weather service said.

"Compared to what we’ve already seen this summer, we haven’t seen anything like this," Brayden Murdock, a forecaster with the weather service, told SFGATE on Tuesday for a story on the Bay Area heat event. "This is our biggest warm-up of the year so far."

Sunday is expected to be the hottest day of the week in the Bay Area with San Francisco hitting an afternoon high of 82 degrees, Oakland 88, San Jose 100, Santa Rosa 102, Livermore andConcord 107, Fairfield 106, Gilroy 109 and Discovery Bay 112.

"Right now, it looks like there will be enough of a marine influence that it won't get too warm in San Francisco," Murdock said. "The more interior areas, that’s where we’re going to get really warm. For people on the coast, it’s not going to take long for you to drive inland and see 100 degree temperatures."

The weather service issued an excessive heat watch for the Bay Area for Saturday through Tuesday. This means conditions may be especially dangerous to heat-sensitive groups and those without easy access to cooling and water.