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

By Mark Memmott / NPR

Published January 21, 2014 at 1:25 AM PST

This story was published more than 10 years ago.

Here we go again. Earlier this month in St. Louis, Jerome Harris bundled up against frigid temperatures. Now, cold air is again rushing south from the Arctic and a "bomb" of a storm is brewing across much of the eastern half of the nation.

From the NPR Newscast: 'Bombogenesis'

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:

Bombogenesis

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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?

Well, as Bolaris says, it's a "rapidly intensifying storm." The conditions that set one off: According to WeatherPrediction.com, "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.

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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" -- is 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.

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