Is It a Blizzard? A Nor’easter? And What’s the Difference?

On March 1, 1888, a buyer for the department store Edward Ridley & Sons in New York City made an error. For $1,200, the buyer, John J. Meisinger, bought a carload of unclaimed wooden snow shovels — 3,000 of them — to sell at the store, the story goes. It was a “ridiculous low price,” Mr. Meisinger later wrote, but strangely timed. “Many of the buyers laughed at the idea of me buying snow shovels at the end of the season,” he said.

Days later, a blizzard of epic proportions had descended on the east of the country. “THE WORST STORM THE CITY HAS EVER KNOWN. BUSINESS AND TRAVEL COMPLETELY SUSPENDED,” read a headline in The New York Times on March 13. Great drifts of snow, in some places 15 feet high, accumulated across the region.

In the end, nearly 400 people died during the Great Blizzard of 1888, including 200 in New York City. Communications, commerce and travel were interrupted for days.

The story ended well for Mr. Meisinger, however, who turned a late-winter profit on his snow shovels. “Ridley’s was the only store that had a large stock of snow shovels and sold every one the first day,” he wrote. “Had the laugh on the other fellows,” he added.

Blizzard. Snowstorm. Nor’easter. What’s the difference?

The storm of 1888 was definitively a blizzard. But what about others? Several criteria must be satisfied for the National Weather Service to use the word “blizzard,” said Eric Guillot, a winter program coordinator for the service.

The term applies only when, for at least three consecutive hours, snow is blowing or falling, winds are at least 35 miles per hour and visibility is a quarter mile or less.

True blizzards are “kind of uncommon,” Mr. Guillot said.

Canada defines a blizzard by slightly different standards, said David Phillips, a senior climatologist at Environment and Climate Change Canada. Below the tree line, where the tundra meets the forest, the criteria for visibility and wind speed are almost the same as the United States’, but the conditions must persist for four consecutive hours to constitute a blizzard there. Above the tree line, in places like Nunavut, Iqaluit, Yellowknife or Whitehorse, “four hours is just not going to do it, but six hours or longer would qualify,” Mr. Phillips said.

Snow doesn’t have to be falling from the sky for a blizzard to occur, Mr. Phillips emphasized. Snow from a previous storm can be picked up by the wind to form a type of blizzard referred to as a “ground blizzard,” he said.

Nor’easters are storm systems that form along the country’s East Coast and whose winds blow from the northeast. Nor’easters tend to be wet, Mr. Phillips said, and therefore less prone to generating the dry kind of snow that reduces visibility, but they can sometimes lead to blizzard conditions. The Great Blizzard of 1888, for example, began as a nor’easter.

How does a blizzard form?

Nor’easters can bring about blizzard conditions, but in the United States, blizzards are most common in the Upper Midwest and the Great Plains, according to the Weather Service.

In these areas, Mr. Phillips said, blizzards can result from weather phenomena known as “Colorado Lows” or, farther north, “Alberta Clippers.” Such storm systems originate east of the Rocky Mountains and move very quickly — like a clipper ship — toward the Plains or the Midwest, he said.

Typically, Mr. Phillips said, the storms also bring “a lot of light, fluffy, dry snow that can get above the ground” and reduce visibility. When they collide with a blast of Arctic air, a blizzard can occur, blowing fiercely over the flat topography of the region, he said.

Where does the word ‘blizzard’ come from?

It depends who you ask. A week after the March 1888 blizzard, The Times was already writing about the word’s etymology. “Blizzard was first used by those who first experienced it while settling in the Western plains,” one article read. “Until bereft of our own or better authority the American theory of the American term for an American storm will hold its own,” it added.

Some believe the term was borrowed from military vocabulary, Mr. Phillips said. “The interpretation that I thought was kind of neat was that it was actually used in the United States back in the 1800s,” he said. “And it referred to a severe blow, like a cannon shot or a volley from a musket.”

The word “blizzard” could also be the result of the convergence of “blister, bluster and blitz,” a lexicographer told The Times in 2023.

How do I keep safe during a blizzard?

Much has changed since 1888, but blizzards can still be deadly.

In December 2022, for example, a blizzard in Buffalo killed 31 people. A team of researchers at New York University subsequently found that emergency warnings from city officials did not adequately convey how life-threatening the storm would be.

The best way to keep safe during a blizzard is to stay indoors, said Mr. Guillot of the Weather Service. Households should prepare to hunker down if necessary and should have an emergency kit with clothing, blankets, enough food and water for three days (along with a can opener), first-aid supplies, batteries, a flashlight, a phone charger and medications, he added.

“Having a NOAA weather radio so you can get the latest updates” can also help, he said, particularly if your cell service dwindles.

If you are at home during a blizzard and lose power and heat, close your blinds or curtains and any interior doors to conserve warmth, Mr. Guillot said. And don’t forget to eat and drink. “That’s the thing I feel like people don’t do, but if you drink, that provides your energy, and keeps you warmer, actually, as you’re digesting,” he said.

If you find yourself trapped in your car during a storm, Mr. Phillips said, “don’t venture out, because you’re going to get disoriented very, very quickly.” Indicate to other drivers and rescuers that you are in your car by switching the vehicle’s dome light on. If your car is buried in a drift, raise a flag or another bright material outside to mark your location, he said.

Trapped drivers should also be mindful of the danger of carbon monoxide poisoning from a blocked tailpipe, Mr. Phillips said. Avoid “running the engine for more than 10 minutes at a time, and make sure there’s a window slightly open,” he said.

Above all, Mr. Phillips said, pay close attention to meteorologists’ warnings. “You can get a forecast on the internet, on your cellphone, on the radio, newspapers, television.,” he said. “The availability of the warning is there, as long as they heed it.”

Kirsten Noyes and Jeff Roth contributed research.