The US is experiencing a striking mix of weather extremes this March. Flooding rains in Hawaii, rare snow in Alabama, flip-flopping temperatures in the north-east and, perhaps most concerning, a severe heatwave affecting the west coast are raising questions about how strange these patterns really are, and what role the climate crisis is playing.
Experts suggested that people around the US need to pay closer attention to the climatecrisis and do what they can to “minimize the impacts”.
Of course, in some ways, the current patchwork of weather activity reflects a familiar seasonal transition: March has long been known for its unpredictability, particularly in regions like the north-east.
“The weather has behaved a lot like I expect it to,” said Jon Nese, associate head of the department of meteorology and atmospheric science at Penn State. “In March, we have some warm days, and then it turns sharply colder and snows. It’s the kind of rollercoaster that we’re used to.”
In New York, Daniel Bader, a program manager at the Consortium for Climate Risk in the Urban Northeast at Columbia’s climate school, described a particularly dramatic swing: “Temperatures at Central Park hit 80 degrees, and then two days later, there were snowflakes in the air.”
“March is kind of an active weather month,” Bader continued. “This kind, where one day it’s very warm, and the next day it cools off quite a bit, is not out of the ordinary.”
The key driver behind these extremes is the jet stream – a fast-moving current of air high in the atmosphere that can sometimes become very wavy. These dips can cause different extremes to happen simultaneously in different parts of the country, such as a ridge of warm air in one region, and a trough of cold air in another.
“The heatwave in the west, happening at the same time as we turn sharply colder in the east, those two things are related,” Nese said.
Bader echoed this explanation, noting that seasonal shifts in temperature gradients influence the jet stream’s position and behavior: “There can be these ridges and troughs that develop and that can be contributing to some of these extreme events.”
But if March has always been a month of extremes, this year’s events suggest that those extremes, particularly on the warm side, are ramping up in severity.
The intensity of the heat in the western US has frequently broken records in recent years, with this past week being no exception. California, Nevada and Arizona were all under heat warnings this week amid scorching temperatures.
In California, the National Weather Service (NWS) said the Los Angeles area was facing “extremely rare heat for March”, warning residents of a high risk for heat illness. Palm Springs, about 100 miles (160km) east of Los Angeles, reached a high of 107F on Thursday. Heat alerts remain in effect through Sunday.
The heatwave scorching the west would have been “virtually impossible” if not for the climate crisis, according to a team of scientists. Global warming, caused primarily by the burning of fossil fuels, has made this kind of heatwave four times more likely to occur over the last decade, according to a rapid analysis released Friday.
“The warmth in the west right now is very unusual,” Nese said. “There are going to be a ton of high temperature records set. Some of the temperatures may actually beat April records.”
Bader was even more direct: “This is really unprecedented conditions. We may break April records. The warmest temperature in March ever recorded in the United States might fall.”
Even isolated anomalies, like snow in the southern state of Alabama, underscore the broader thread of variability. Several other states, including Wisconsin, Minnesota and Michigan, saw snowfall go well into the double digits.
On Tuesday, half a million US homes and businesses were without power after a potent storm system brought a mix of snow, strong winds, cold temperatures and rainfall to areas from the midwest to the east coast.
Nese said: “Snow in Alabama in March is pretty unusual.”
The overlap between unusual snowfall and the climate crisis is complex and still being studied, but there is clearer consensus when it comes to heat.
“It’s probably reasonable to say that this heatwave in the west in March will have a climate change fingerprint on it,” Nese added.
Bader similarly emphasized that while individual events are difficult to attribute, broader trends are clearer: “The greatest connections we can draw are related to extreme heat events becoming more frequent and also more intense.”
He also explained that the increasing heat of the atmosphere could intensify rainfall. Bader said: “A warmer atmosphere can hold more moisture that could potentially lead to more heavy precipitation.”
While the climate crisis might have some effect on bringing unusually colder weather in certain regions, the number of record-breaking heatwaves is greatly outpacing the number of cold weather events as the planet continues to heat up.
This summer is expected to be among the hottest on record, continuing the trend of record-shattering heat driven by the climate crisis as well as the potential development of a strong El Niño.
And as the extremes become more and more unpredictable, experts stress the importance of preparedness, even as Donald Trump has cut funding to the Federal Emergency Management Agency (Fema), marking a dangerous erosion in US capacity to prepare for and respond to natural disasters.
“These events are kind of constant reminders that we are very vulnerable to weather and climate extremes,” Bader said. “If there are opportunities to minimize the impacts, then we should take advantage of those.”
