What Is This Bombogenesis And Why Is It Dumping Snow On Us?

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    A man crosses the street Tuesday in Philadelphia. A fast-moving cold front will plunge the Northeast into a deep freeze and dump up to a foot of snow in certain regions, forecasters said.
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    Trucks with snowplows line up on a ramp near Interstate 95, as motorists make their way around in Weston, Mass. Heavy snow has been forecast and a blizzard warning was posted for portions of Massachusetts, prompting Gov. Deval Patrick to dismiss nonemergency state workers early.
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    A woman walks through the snow in Hoboken, N.J.
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    Bashon Mann and his children sled down a hill at the Capitol as snow falls in Washington, D.C. Students and government workers were told to stay home while the winter weather hits the Mid-Atlantic region.
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    People walk in a park along the Hudson River across from New York City as snow begins to fall in Hoboken.
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    Rick Mendenhall of Albuquerque, N.M., throws a snowball during a snowball fight with friends on the National Mall in Washington, D.C. Thousands of flights were canceled, students got an extra day off from school, and the federal government closed its offices in the Washington area Tuesday.
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    Pedestrians make their way through the snow in New York's Times Square.
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    A snowplow tries to keep lanes clear in Philadelphia. According to the Weather Channel, the snowy weather will be affecting tens of millions of people in one of the nation's most-populated stretches.
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    A man crosses the street as snow falls in Baltimore.
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Just as we're getting used to hearing about the polar vortex, there's another cool-sounding weather term being thrown around that we've had to look up:


This post by Philadelphia meteorologist John Bolaris caught our eye: "Old Man Winter to drop bombogenesis."

It led us to a 2010 piece by Weather Channel meteorologist Stu Ostro, who wrote that though he "couldn't find 'bombogenesis' in the [American Meteorological Society] glossary, [it's] a term commonly used by meteorologists."

So what is it?

From the NPR Newscast: 'Bombogenesis'

Flight Delays

The website FlightAware tracks flight delays and cancellations here. As of midday, there had been more than 1,200 delays and more than 2,770 cancellations of flights into or out of the U.S.

Well, as Bolaris says, it's a "rapidly intensifying storm." The conditions that set one off: According to, "bombogenesis typically occurs between a cold continental air mass and warm ocean waters or between a cold polar air mass and a much warmer air mass."

Those air masses mix together to form an "extratropical surface cyclone" — or, as in this case, a "bomb" of a storm.

Cyclones, as we've said, are "rotating storms spawned in the tropics." An "extratropical cyclone," though, has cold air at its core and can form over land or water, as The Weather Underground says. Bombogenesis also draws its name from another weather term — cyclogenesis — which is basically a fancy word for a cyclone's origin.

This bombogenesis blather comes, of course, because of what's expected to happen today from the Mid-Atlantic up into New England. There's going to be "moderate to locally heavy snow from the central Appalachians to southern New England, including all of the Mid-Atlantic region," the National Weather Service says. The storm — and the "bomb" — are being fueled by another blast of cold air from the North that's running into warmer air coming up from the South.

The forecast for 5 inches or more of snow today in the Washington, D.C., area has led to the shutdown of federal offices in the nation's capital. Schools are closed in cities and towns across the affected areas.

As The Weather Channel adds, the wicked weather will be affecting tens of millions of people in one of the nation's most-populated stretches.

Update at 8:45 p.m. ET: Cancellations Top 3,000

According to the FlightAware tracking site, a total of 3,011 flights were canceled inside the U.S. today, with more than 200 each originating at the Philadelphia, New York's LaGuardia, and Newark airports (the site also lists cancellations by destination airport).

Our original post continues:

Let us know how you fare as this bombogenesis blows through. And let us know if there are other weather terms you think are particularly interesting.



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