Fourth of July is coming in hot, as dangerous heat dome brings triple digit temps

The triple-digit holiday heat wave has arrived.

Southern California is expected to get scorched starting Tuesday throughout the next week, sparking excessive heat warnings and heat advisories for much of the region.

Gov. Gavin Newsom said in a statement that while we’re used to hot temperatures here in California, this heat wave is serious and will bring little overnight relief.

“As we come together this week to celebrate the Fourth of July, look out for each other and take steps to stay safe,” Newsom said in a statement. “Don’t let this heat catch you by surprise, California.”

What to expect from the forecast

While the coastal areas are expected to stay relatively cool with temperatures in the upper 80s and lower 90s, it’ll really heat up as you move further inland.

The valleys are expected to be in the upper 90s with a peak around 108 degrees, and the mountains could climb even higher to 112 degrees.

The deserts could get dangerous with highs between 110 and 118 degrees, according to the National Weather Service.

Friday and Saturday are expected to be the hottest days until the summer sun starts to ease up early next week.

Ariel Cohen, meteorologist in charge of the National Weather Service Los Angeles / Oxnard, told AirTalk a large heat dome is setting up offshore, bringing a longer period of extreme temperatures to the western U.S.

“So what we're seeing right now is the airflow around that heat dome is causing it to be blocked off from any motion, and so it's going to keep the very energetic and very heat-favoring environment over Southern California for quite a while,” Cohen said.

Excessive heat warnings have been issued for the Santa Clarita Valley, the San Fernando Valley, the Santa Monica Mountains, the Ventura County Mountains, and the Antelope Valley, among others, until at least 6 p.m. Monday.

The Ventura and Los Angeles counties inland coasts, including downtown L.A., are under a heat advisory until 6 p.m. Sunday along with Pasadena, El Monte, and the rest of the San Gabriel Valley.

The Orange County inland areas, as well as the Santa Ana Mountains and foothills, are also under a heat advisory until 9 p.m. Saturday.

We should get a bit of a break about a week from now around Monday or Tuesday, Cohen said, but there’s still a lot of uncertainty with the heat dome.

Tips for keeping cool

Cohen said these are certainly “very dangerous conditions” setting up over SoCal, and while we’ve seen these kinds of temperatures before, people need to be prepared.

“This is an extreme event, and everyone needs to take precautions, because the decisions that you make regarding this event, making sure that you're taking those heat safety precautions, that you're not leaving anyone unattended in the vehicle can save your life,” he said.

Officials recommend staying inside between 10 a.m. and 3 p.m. to avoid the most blistering heat. You can also help cool your home by keeping the windows covered, strategically placing fans, and setting the air conditioning between 75 and 80 degrees.

But if you don’t have AC or a home to retreat to, you can find the nearest public cooling center in L.A. County here.

You can find more information on Orange County’s cooling centers here, Riverside County’s here, and others throughout the state here.

Los Angeles Public Library branches can also help you escape the heat during their regular business hours, and you can find a full list of locations here.

Drink plenty of water, about two or four glasses each hour. You can find the nearest free hydration station at parks across the city here.

Once you’re all set for the sun, check on your neighbors who might be vulnerable to the extreme heat, especially if they don’t have air conditioning or if there’s a power outage.

That extends to furry friends too. Try to keep your pets indoors, but if they have to hang out outside, make sure they have plenty of water and access to a shaded area.

Never leave animals or humans alone in the car, even with the window cracked.

Saguaro National Park rangers in southern Arizona demonstrated the danger of a hot car by baking banana bread on the dashboard last week, with temperatures reaching 211 degrees by mid-afternoon.