What is a nor'easter?
Forecasters reserve the term for storms that threaten lives and property along the Eastern Seaboard. But the official definition is narrower (and stranger) than most people assume.
Providence, Rhode Island, shattered one-day snowfall and storm total records, but this entire winter is blowing historical averages away throughout much of the Northeast.
When a nor'easter takes aim at the mid-Atlantic and Northeast coasts, it may not produce a single snowflake.
Despite what the name suggests to most people, snow has nothing to do with it. A nor'easter is any large storm that drives winds from the northeast along the Atlantic coast of North America.
Waves churned up by a nor'easter smashed into a seawall in Scituate, Massachusetts, on Oct. 27, 2021, crashing down on the roofs of waterside homes.
That tends to surprise people, because the word arrives carrying a lot of freight, "The Storm of the Century," "The Perfect Storm," angry seas and sinking boats. This is roughly why AccuWeather meteorologists reserve the term for the storms that actually warrant it: the ones expected to threaten lives and property.
What actually makes a storm a nor'easter
A nor'easter is any large storm that drives winds from the northeast along the Atlantic coast.
A nor'easter is defined by the coastal wind direction and not much else. Somewhere inside a big storm's circulation, winds will always be blowing from other directions, that doesn't disqualify it. What matters is the flow moving along the shoreline, which, as the storm swirls just off the coast, often means the hardest-hit coastal towns have winds howling from the northeast.
Three things people assume are requirements for a nor'easter but aren't:
1. Snow. Plenty of nor'easters deliver nothing but wind-driven rain.
2. Blizzard conditions or damaging wind. The strongest storms bring both. Neither is part of the definition.
3. Moving toward the northeast. Nor'easters stall, drift and occasionally wander in the wrong direction entirely. The name describes where the wind comes from, not where the storm is going. This is the single most common misconception forecasters have to correct.
How they turn dangerous
Four inches of snow covers piles of debris from Superstorm Sandy in Point Pleasant Beach, N.J. on Thursday Nov. 8, 2012, a day after a nor'easter hit the storm-weary state. Emergency dunes seemed to have held during the recent storm, and flooding that had been feared did not materialize. (AP Photo/Wayne Parry)
Nor'easters gather strength along sharp temperature contrasts (cold fronts) draped across the eastern United States. The real acceleration comes when one runs up against high pressure parked over southeastern Canada or northern New England. The gap between the high and the storm's low center tightens, and the winds respond. In the most extreme cases, they approach hurricane force, 74 mph or greater, in a system that is not tropical in any respect.
The elements of a nor'easter set up.
If the storm's central pressure falls fast enough, 24 millibars, or 0.71 of an inch of mercury, in 24 hours, it earns a second label: bomb cyclone.
Add sufficient cold air and the snow can accumulate at several inches an hour. The heaviest bands sometimes arrive with thunder.
When do nor'easter happen?
Technically, a nor'easter can form any month of the year if all the elements are there, but the season runs from September through April, when nor'easters are more frequent and severe. A late-September storm is early but not unheard of.
The hazard list is long and tends to show up in combination: flooding rain, heavy snow, damaging wind, rough surf, beach erosion and coastal flooding. Compact nor'easters have hammered the immediate coastline while the central Appalachians, a couple hundred miles inland, stayed dry and sunny.
Storms people still talk about
The Perfect Storm on Halloween 1991. The remnants of Hurricane Grace merged with a non-tropical storm out of the Canadian Maritimes. Seas offshore ran as high as 100 feet; winds hit 70 mph. "You just had the pounding of the coast for three days in a row or more," AccuWeather Senior Meteorologist Dave Dombek said. A novel and a George Clooney film followed.
The Blizzard of 1993. Known since as the Storm of the Century, it buried a huge swath of the East under 1 to 3 feet of snow, with Appalachian drifts as tall as single-story houses. A dozen states declared emergencies. Damage estimates reached $6 billion to $11 billion, and more than 300 people died.
March 2018. Four nor'easters in three weeks. The first dropped more than 2 feet of snow in places; New England absorbed the worst of the next two. At the peak, 1.6 million customers lost power between North Carolina and Maine, and the storm surge rivaled Superstorm Sandy's.
The campaign to abolish the word
Not everyone appreciates the term. Some New Englanders regard the contraction as an affectation, and one of them made a project of it. Edgar Comee, a former editor at the Portland Press Herald living in Brunswick, Maine, spent his later years mailing postcards to hundreds of journalists in his capacity as chairman of the Ad Hoc Committee for Stamping Out Nor'easter, a committee of one. He dismissed the word as the habit of landlubbers hoping to seem "as salty as the sea itself."
Forecasters kept using it anyway and for a defensible reason. When the word turns up in a forecast, people on the coast stop and read it.
Report a Typo
