Extreme heat is straining Texas's power grid and fueling Yosemite fires. It's forecast to last 2 more weeks.

• A heat wave is breaking records across the US, threatening giant sequoias and Texas's power grid.
• Forecasters say the heat will likely continue for another two weeks, until the end of July.

The US is suffering through another multi-week heat wave, which is forecast to last nearly the entire month of July.

Several days of triple-digit temperatures strained Texas's power grid, prompting the Electric Reliability Council of Texas (ERCOT) to ask customers to limit power use. Wildfires are roaring through Yosemite National Park, fueled by high temperatures that dry out vegetation. The blazes have threatened ancient giant Sequoias.

About 50 million people were under a heat alert in the US last weekend, USA Today reported. Though that number had dropped to 24 million as of Friday, the extreme temperatures are not over yet.

The heat will likely continue across the US for the rest of July, and expand again to the West Coast, according to forecasts from the Climate Prediction Center, which is operated by the National Weather Service (NWS) and the National Oceanic and Atmospheric Administration. The below map shows the center's projections.

Over the next two weeks, the high-pressure system that's currently trapping heat over Texas will move west toward California, according to climate scientist Daniel Swain.

"This will bring an extremely broad region of hotter than usual temperatures to the entire western 2/3 of the country," Swain said in a Twitter thread with forecast imagery from the European Centre for Medium-Range Weather Forecasts.

He added that the coming heat wave will be "remarkable," both due to the vast land area it covers and its duration. Because it coincides with a pessimistic rain forecast, Swain said that the next two weeks of heat are likely to accelerate fire season.

Extreme heat kills hundreds of people across the US every year. Heat waves are growing more common, severe, and lengthy as global temperatures rise. The 2018 National Climate Assessment found that the frequency of heat waves has tripled since the 1960s, and that the average heat-wave season has increased by 45 days.

So far, this summer is doing its best to demonstrate that trend. The Climate Prediction Center also produces a three-month outlook for temperatures nationwide. That forecast projects a summer of above-average heat across the entire US, with the exception of two small pockets in the north.

"I don't think we're going to have record temperatures continue every day or every week through the summer. But I think what this suggests is that the conditions will be favorable to see at least rounds of well-above-normal temperatures at times through the summer," Marc Chenard, a meteorologist with the NWS, previously told Insider.

Indeed, this week's temperatures come on the heels of an exceptionally hot June. Before summer even began, heat had shattered daily temperature records across the country, forced school closures, cost at least three human lives, and killed more than 2,000 cattle. The June heat wave, too, was remarkable for how long it lasted and how far it spread.

The US isn't alone in its heat-wave plague.

Extreme heat has battered the planet all summer

Europe and China are also experiencing their own record-breaking heat waves — again. Just like North America, those regions suffered through a sweltering June of record-high temperatures. North Africa, the Middle East, and other parts of Asia are facing record heat, too.

"This large area of extreme (and record breaking) heat is another clear indicator that emissions of greenhouse gases by human activity are causing weather extremes that impact our living conditions," Steven Pawson, chief of NASA's Global Modeling and Assimilation Office, said in a statement.

As the high-pressure systems that trap heat rolled in and baked the land, fires also broke out in Spain, Portugal, Morocco, and Tunisia.

In Italy, the heat helped trigger the collapse of a portion of a glacier in the Dolomite mountains, leading to a glacier avalanche that killed 11 hikers. Spain's Health Ministry said the heat there has killed 84 people already in July, following a staggering 700 heat-related deaths in June.

On Friday, the UK declared a national extreme-heat warning for the first time ever, in anticipation of temperatures exceeding 104 degrees Fahrenheit next week.

AccuWeather meteorologists warned on Wednesday that this could become Europe's worst heat wave in 200 years. It could last through the end of the month.

In China, the heat accompanied deadly floods, another extreme weather event that is becoming more common and more severe in many parts of the world as the climate changes.

In June, Japan experienced its worst heat wave on record. India and Pakistan suffered a 100-day heat wave earlier this year.

In the Northern Hemisphere, there are still two months left of summer.