There’s That Word Again: “Bomb”

March 1, 2018 · 0 comments

It’s like the word du jour. Or, more accurately, THE word du storm.

It seemed like every time this winter that a big East Coast storm—a significant nor’easter—looked impending in computer models, the media hype machine cranked out the word “Bomb.” Or “bomb cyclone.”

And here it is again:

Destructive Nor’easter Emerging; Expected to ‘Bomb Out’” weather.com trumpeted Thursday morning about Friday’s storm.

Bomb Cyclone: MA Town Orders Voluntary Evacuations” the Falmouth Patch splashed on its online front page. (Ponder that additional hype for a moment: order “voluntary evacuations.”)

Another ‘bomb cyclone’ — with a huge flood risk — is aiming for the Northeast” buzzed CNN.

Bomb cyclone. As in meteorological bomb. Short for bombogenesis. Not a fiery explosion, but rather an explosive—as in extremely rapid—deepening or lowering of atmospheric pressure in the center of the storm. A drop of at least 24 mb in 24 hours. That ramps up big winds.

This time, though, the term may be apropos. And not just meteorologically.

While the pressure in tomorrow’s nor’easter is expected to plunge from about 1006 mb to 975 mb—31 mb—from Thursday night to Friday night, meeting the definition of bombogenesis, it’s the formidable eruption of hazardous weather—high winds, heavy rain and snow, and coastal flooding, potentially major to even severe coastal flooding, the NWS in Boston says—that will define this particular storm.

The storm will generate high winds from the mid-Atlantic to eastern New England, gusting 50-60 mph in many areas and possibly to 75 mph hurricane force in southeast New England and on eastern Long Island. For a long time, as strong high pressure over Greenland (that incidentally has brought stunningly warm air to the Arctic) slows the storm’s departure.

These northeast winds will persist through three high tide cycles, some of the highest tides of the month, contributing to minor to major coastal flooding from Maryland to Maine, as detailed in a blog post by the Weather Underground. And with 2-3 feet of storm surge combined with 20-30 foot waves just offshore and tides Accuweather says are already running 2-4 feet above normal, there’s a small chance that flooding at the coast could be severe and widespread—”a very dangerous situation that may require evacuations,” the NWS in Boston stated in its 5 a.m. Thursday Area Forecast Discussion.

Add to that 2-4 inches of rain likely to worsen snowmelt flooding across much of Southern New England and more than a foot of heavy, wet snow in the higher elevations of the Northeast, and Friday’s nor’easter looks set to do some damage. Power outages from the winds and snow are likely.

We’ve posted about meteorological bombs before, here and here. This time, this nor’easter might just live up to the hype.