Get ready for a year of chaotic weather in the United States

Despite its announcement 2025, the third hottest year on record, has been a relatively quiet year for climate disasters in the United States. No major hurricanes made landfall, while the total number of acres burned in last year’s wildfires — a way to measure the severity of a wildfire season — fell below the 10-year average.

But starting this week, the West is experiencing what appears to be an unprecedented heatwave, while forecast models predict that a strong El Niño is likely to emerge later this year. These two unrelated phenomena could set the stage for a prolonged period of extreme and unpredictable weather that could arrive next year, exacerbating the effects of a climate that is becoming hotter thanks to human activity.

First, there is the heat. Starting this week and heading into next, a massive swath of high-pressure air will send temperatures soaring to record highs in the American West. The National Weather Service predicts that record temperatures across multiple states are set to be broken in dozens of locations, extending as far east as Missouri and Tennessee. The NWS issued heat warnings for parts of California, Arizona and Nevada, as well as fire warnings for parts of Wyoming, Nebraska, South Dakota and Colorado.

“This will be the strongest ridge we have observed outside of summer in any month,” says Daniel Swain, a climate scientist at the University of California Agriculture and Natural Resources University.

The other striking thing about this heat wave is how long it will last, Swain says. “This is not a day or two of extreme heat,” he says. “In some of these places we have already seen record highs every day for a week, and we expect to see them every day for at least another seven to 10 days.” The end of March will be even more severe, with temperatures in some places exceeding the records set in April and May. “There aren’t many weather patterns that can produce 85 or 90 degrees in San Francisco, Salt Lake City and Denver in the same week.”

This late-winter heatwave adds to an already warm winter in the West, with major implications for the summer. A month ago, snowpack levels in several states reached record levels thanks to warmer than average temperatures. According to data provided by the Department of Agriculture, snow levels are still 50% below average in many western states. The Snowpack is an important natural reservoir for rivers in the West. In many areas, 60 to 70 percent of the region’s water supply comes from snowmelt. The reduced snowpack is a bad sign for already stressed rivers like the Colorado, which supplies water to 40 million people in seven states.

Swain says the ongoing heat wave will likely make conditions worse. “April 1 is usually the point where snow peaks, at least historically,” he says. Even if temperatures cool into summer, these low snow levels are also a worrying sign for the upcoming fire season. Snow droughts like those experienced in the West can dry out soil, kill trees, and reduce river flows: ideal conditions for wildfires to grow. Meanwhile, water supplies in the Colorado River may decline to lower levels. Countries that depend on the river are already facing a political crisis as they try to renegotiate their water rights. Drought will only up the ante.

Then there is El Niño. Last week, the National Weather Service announced that there is more than a 60 percent chance that El Niño will develop in August or September. Various weather models indicate that El Niño may be particularly strong. While we probably won’t know for sure until the summer, “the fact is that… [all the models] “The upward movement is something to behold,” says Zeke Hausfather, a research scientist at Berkeley Earth.