A high pressure system, known as a thermal dome, lingers over the Southwest USAwill push the mercury in the region well above 38 degrees Celsius today, leaving millions of Americans facing heatwave conditions in the coming days.

The U.S. Weather Service has issued extreme heat warnings and advisories through Saturday for about 30 million people from Northern California, south to Arizona and east to Texas.

The same area last summer was faced with conditions for weeks extreme heat.

“It’s just really hot,” said Michelle Reynolds, 52, who was walking her dog Scott in a park in Modesto, California. “The weather is not only hot for us, but also hot for the animals».

Reynolds reckons the seasonal heat seems to be getting worse every year.

“You just don’t know how the climate is going to change,” he noted. “We’re going day by day. That’s all we can do.”

The maximum temperature is expected to reach 44 degrees Celsius in the Las Vegas area today, which could be a record for June 6. And that will be “cooler” compared to conditions expected in Death Valley, California, where the mercury is expected to top 49 degrees Celsius by afternoon.

In Phoenix, Arizona’s capital of 1.6 million people, highs are expected to reach 45 degrees Celsius, with authorities opening air-conditioned rooms in libraries and near some popular hiking trails during the day.

“High temperatures continue and records may be broken in the next two days,” says the US Weather Service in Phoenix in a post on the X platform.

Some cities in the region experienced their hottest summer of 2023. In Phoenix, the high temperature was 43 degrees Celsius for 55 consecutive days, a record for the city, where 645 people died in the metropolitan area from heat-related illnesses last summer .

Forecasters are warning residents in affected areas to stay indoors, drink plenty of fluids and check on neighbors and loved ones if they can.