Life was different in the 1950s. Homes cost less than a quarter of what they do now. Living room TV screens weren't much bigger than a modern laptop. Construction was starting for the Glen Canyon Dam. Humans had yet to travel to space.
Someone who grew up back then can tell you something else: Winters were colder and longer.
Over the past seven decades — the span of the average human life — the number of freezing days has shrunk by weeks in most places across the United States.
Minnesota: Dog sledding, ice fishing, pond hockey
“If you're going to live here, you can either shut yourself in for six months, or you can find a way to thrive. And a lot of people do that,” said Kenny Blumenfeld, a senior climatologist at the Minnesota State Climatology Office.
But winters in the Midwestern state are not what they used to be. On average, they are getting warmer.
It doesn’t mean every winter is warmer than the last, Blumenfeld said, adding that there are ups and downs from natural events like El Niño, but for a state that relies so heavily on winter, the inconsistency can still have consequences.
“It's kind of like [an] unnerving sense where we can't depend on winter,” Blumenfeld said.
Warmer winters have disrupted many events, big and small. In 2025, the John Beargrease Sled Dog Marathon, a 300-mile race, was postponed for two months because the lack of snow and ice had made the course unsafe. In 2024, the U.S. Pond Hockey Championships, in Minneapolis were canceled because warm weather made the lake ice unplayable. In neighboring Wisconsin, the American Birkebeiner ski race also has been shortened and canceled in recent years.
Minnesota’s lakes have lost an average of 10 to 22 days of ice cover in the past century, according to the Minnesota Pollution Control Agency.
Though the season is still long enough to go ice fishing, the timing of the freeze is also important. For example, if it's not icy by the time winter break starts, some people might cancel reservations at cabins, Blumenfeld said.
'One-two punch' on snowpacks
Our analysis shows that in cities that had fewer freezing days, the coldest temperature of the season has increased by an average 5.7 degrees since 1956.
And when temperatures get warmer, that’s bad news for snowpacks.
“The warmer your atmosphere is, the more likely you’re going to get closer to that melting point, and you’re going to start seeing more of that winter precipitation falling as rain instead of snow,” said Elizabeth Burakowski, a research assistant professor at the University of New Hampshire. “That has a one-two punch on a snowpack.”
When snow falls on snow, it accumulates. But when rain falls on snow, it can accelerate melting. White snow is bright and reflective, but as it melts, it exposes darker ground underneath. This absorbs more of the sun’s energy, warming and melting the snowpack in what is known as the albedo feedback loop.
Towns and cities across the country rely on winter activities like skiing, snowboarding and snowmobiling to support their economies. Cold, snowy days are a basic requirement.
Even considering the cold chill in the East at the start of the winter, the contiguous United States had its second-warmest winter in 131 years of recordkeeping, according to the National Oceanic and Atmospheric Administration.
In January, Vail Resorts CEO Rob Katz told investors that season-to-date skier visits were down 20% compared with last year. In the Rockies, 11% of terrain was open in December.
The vast majority of resorts use snowmaking, which sustains about 1 in 6 skiable acres, to run their operations, according to a report from the National Ski Areas Association.
Though it can help during years when not enough snow falls, temperatures still need to be cold enough – a couple of degrees below freezing if the humidity is low, but ideally colder.
Colorado researchers and consultants had projected that shorter winter recreation seasons could lead to the loss of millions to tens of millions of visits annually by 2050 in the state and around the country.
Less water, more fires
Communities across the West are preparing for water restrictions this year – including those that control how often people can water their lawns, how often their sheets are washed at hotels, and whether they are served water when they eat at a restaurant.
And the effects of drought can be felt long after winter is over. A recent study found that an earlier spring snowmelt contributes to a longer fire season with more area burned, and that lower snowpack accumulation can lead to more severe fires in the West.
More ticks and mosquitoes
As the frozen season shrinks, some insects and animals are thriving – much to human dismay. The range of bark beetles has exploded, allowing them to ravage more forests.
“Because of warming, we’re getting fewer frost days which, would provide these killing temperatures for these kinds of pathogen species, so they are able to survive in these areas where historically they weren’t able to occur,” said John Kimball, an ecology professor at the University of Montana.
Ticks, which carry Lyme disease, have been marching north and west. A 2019 paper noted that most ticks are active from “the time that the snow melts in the spring until the reappearance of the snow cover in the fall.”
Increased temperatures lengthen the season when ticks are active, increase their survival rate and expand their habitat.
Lyme disease can cause rashes, fever, facial paralysis, and muscle and joint aches, according to the Centers for Disease Control and Prevention.
Some mosquitoes also benefit from warmer winters.
“They don’t regulate their own body temperature, so whatever temperature it is outside is the temperature that the mosquitoes’ body is, and its metabolism depends on that temperature,” said Erin Mordecai, a Stanford associate professor of biology.
In the U.S., West Nile virus is now the most common mosquito disease, but it wasn’t always like this. It was first discovered in Uganda in 1937 and only at the turn of the century it got to New York. According to the CDC, it’s been reported in every state since then.
The virus can cause flu-like symptoms, but severe cases can end up with hospitalizations and death.
For an upcoming paper, Mordecai and her team looked at temperature, mosquito surveillance and human case data in New York for the quarter century after the West Nile virus first appeared there.
“You kind of get to this point in the springtime, where it goes from below 16.7 (degrees C) to above, and when that point is happening has been starting earlier and ending later in the year,” Mordecai said.
The researchers found that warmer temperatures have expanded the transmission season by 20 days, a trend that was more likely to occur because of climate change.
A sweet and fickle harvest
"I always say, if you ever wanted to see God say 'Hold my beer and watch this,' you try to make maple syrup," said said Blackman’s sister Jennifer Reisenbichler, sugarmaker and co-owner of LM Sugarbush in Salem, Indiana. “This is the hardest job I've ever had, if you can call it a job, because no matter what you do, you really can't control the outcome of each season."
In parts of New England, local governments gather with residents on Town Meeting Day in early March to vote on things like town budgets. Historically, it also marked the time of year when farmers would tap maple trees for sap, but over the decades as winters have warmed, that has been shifting earlier.
“If you wait until Town Meeting Day tap, you’re probably going to lose some of the season – you're not going to capture all the sap that you could,” said Steven Roberge, who works at the forestry extension of the University of New Hampshire.
Now, tapping starts on Presidents’ Day or Valentine’ Day.
To produce sap, maples need to go through a daily freeze-thaw cycle, which is why snow is crucial to the forest. It acts as insulation to protect the tree roots from getting too cold. It also moderates warm temperatures, because if it gets too warm, it can end production sooner.
“You can imagine being in New England during colonial times and prior with Indigenous people... Sugar was probably really important,” Roberge said, adding that up until the early 1900s, most of the production was for maple sugar, not syrup, because that was easier to store.
Though the season sometimes gets compressed from two months of normal sap flow into four or six weeks, advances in technology have helped the industry keep up.
Rather than just letting sap drip into a bucket, farmers now use tubing systems with vacuums to speed up the process.
Maple sap has about 2% sugar content. It’s boiled to remove water until it hits about 67% to form syrup. Reverse osmosis, the same technology used to desalinate seawater, removes some of the water from sap and shortens the boiling process.
Research is being done on alternative syrups such as those from sycamores and birch trees – but those don’t taste the same.
Roberge remembers growing up in northern New Hampshire, where every second-grade class would tour a friend’s family sugar house to experience the iconic activity.
“If something would happen to sugar maples, it would be devastating for a lot of people financially," he said. "But I think just from a cultural standpoint, it would be a huge loss here in the Northeast.”
Thinking about how North Carolina, which has a different climate from his home state's, can produce maple syrup makes him optimistic.
“Despite the headlines of climate change, I think there’s always going to be the weather in New Hampshire that will be able to harvest sap,” Roberge said. “But it just won’t be the same as it was 100 years ago.”
Search for your county
Explore the map below to see how many freezing days we experience now compared with 1956.
How we did it
We used a daily temperature dataset from the National Oceanic and Atmospheric Administration called nClimGrid-Daily. It provides estimates for square areas about 5 kilometers wide (roughly 3 miles). For every U.S. city or town with a population over 100,000, we used the data from the grid cell closest to its center. We then identified each day that the low temperature reached 32 degrees Fahrenheit or colder. We grouped these freezing days by “water year,” which runs from Oct. 1 through Sept. 30 of the following year (think of it as the fiscal year used in climate and water research).
For each city and year (1956-2025), we measured several indicators: the total number of freezing days, the first and last freezing day of the season, the longest stretch of consecutive freezing days, and the coldest temperature recorded. To understand how these measures have changed over time, we ran linear regressions for all cities that had sufficient data, which we defined as at least one freezing day in at least half the years – mirroring methods used by Climate Central and other researchers.
This approach helps distinguish long-term changes from natural year‑to‑year variability. We also tested whether the trends were statistically significant. We repeated a similar analysis at the county level. Counties that do not experience freezes every year were included to allow for broader exploration of the data. You can read a full description of our methods and find our code on GitHub.
Contributing: Sophie Hartley and Grace Hollars, The Indianapolis Star; Jennifer Borresen, Alberto Cuadra, Trevor Hughes, Karina Zaiets, and Shawn J. Sullivan, USA TODAY.
Additional photography: Scott Olson, Getty Images; Forrest Brown, Cheney Orr and Anney Yang.


