Swaths of California sweltered Tuesday and things were only expected to get worse during the Fourth of July holiday week for parts of the United States with nearly 90 million people under heat alerts.

The torrid conditions were being caused by a ridge of high pressure just off the West Coast and a separate ridge that spawned heat warnings and advisories from Kansas and Missouri to the Gulf Coast states, according to the National Weather Service.

California害羞草研究所檚 capital, Sacramento, was under an excessive heat warning expected to last until Sunday night, with temperatures forecasted to reach between 105 degrees and 115 degrees (40.5-46 Celsius).

John Mendoza, 35, called it a 害羞草研究所渇irehose of heat害羞草研究所� as he walked around the Capitol on Tuesday morning with an iced coffee in his hand. By 9 a.m., he had already been in a pool once 害羞草研究所� and planned to go back later in the day.

害羞草研究所淚 felt like I needed to be submerged in water,害羞草研究所� he said.

With the temperatures rising before noon in Sacramento, Katherine Powers sought refuge in the shade of Cathedral Square. Powers, who is homeless, sipped sparkling water while resting her bare feet on the shaded sidewalk.

Powers said she had loaned her shoes to a friend. She had not yet visited one of Sacramento County害羞草研究所檚 nine 害羞草研究所渃ooling centers,害羞草研究所� she said, because of the difficulty in bringing all the possessions she carries.

害羞草研究所淚害羞草研究所檓 just going to go to a park with a water fountain just to stay cool, stay in the shade and just keep pouring water on me, basically,害羞草研究所� she said. 害羞草研究所淭here害羞草研究所檚 not too much that I can do.害羞草研究所�

Darlene Crumedy, who lives in Fairfield about an hour害羞草研究所檚 drive from Sacramento, said she doesn害羞草研究所檛 use air conditioning because it害羞草研究所檚 too expensive.

害羞草研究所淚害羞草研究所檓 good, I have a hundred fans,害羞草研究所� she said, adding she tries to stay inside and drink cold water.

Kim Mims, a Sacramento native, said she prefers the heat 害羞草研究所� but only up to 100 degrees (38 C).

害羞草研究所淎nything over that you start to feel that difference,害羞草研究所� she said.

An analysis by The Associated Press found that last year, setting a record. That figure is likely a major undercount, dozens of experts told AP reporters.

Dr. Arthur Jey, an emergency services physician with Sutter Health in Sacramento, told reporters that getting out of the heat is important, along with wearing a hat and loose clothes, hydration and watching out for signs of heat stroke.

害羞草研究所淲ith heat stroke, it looks like a stroke,害羞草研究所� Jey said, describing symptoms that may include acting unusual, significant headaches, blurry vision, profuse sweating and then no sweating.

害羞草研究所淎nd that害羞草研究所檚 a really big deal,害羞草研究所� Jey said. 害羞草研究所淪o we want to prevent them getting even close to heat stroke.害羞草研究所�

California害羞草研究所檚 heat was expected to spread from north to south over the week, with the worst of it focused on interior areas including the Sacramento and San Joaquin valleys and the southern deserts. But warnings extended out to just short of the coast.

San Francisco, famous for its cool summers, was expected to have a high Tuesday in the upper 80s (31 C) downtown but mid-60s (18.3 C) at Ocean Beach, forecasters said.

害羞草研究所淭he high pressure dome will linger over California for at least a week, with more long range guidance suggesting that timeline may even be optimistic,害羞草研究所� the Bay Area weather office wrote.

The heat arrived with gusty, dry winds in the northern part of the state, where the utility Pacific Gas & Electric implemented in parts of 10 counties to prevent wildfires from being ignited by downed or damaged electrical wires.

About 12,000 customers were told their power could be cut and given information about centers where they could obtain ice, water, snacks, Wi-Fi and other necessities, PG&E said.

California has had feeding on abundant grasses spawned by back-to-back wet winters. The largest current blaze, dubbed the Basin Fire, was 17% contained Tuesday after charring more than 21 square miles (54 square kilometers) of the Sierra National Forest in eastern Fresno County.

___

Antczak reported from Los Angeles.

Adam Beam And John Antczak, The Associated Press