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Winter Storm Grayson: How a Bomb Cyclone Delivers Freezing Cold Temperatures

A commuter makes her way to work in sub-zero temperatures on Jan. 2, 2018 in Chicago, Illinois. Scott Olson—Getty Images

It’s about to get a lot colder for residents living in the northeast and midwest regions of the U.S. And that’s after winter storm Grayson delivers snow, ice, and wind to the mid-Atlantic and northeast. Meanwhile, another front in the Great Lakes is ensuring folks living in Minnesota, Wisconsin, and Illinois will enjoy periods of snow, followed by bitterly cold temperatures as well.

What’s Happening Now

Winter storm Grayson is already delivering freezing rain and snowy mix to the southeast, even as far south as north Florida. Some theme parks, like Disney’s Typhoon Lagoon Park are closed through Thursday because of the unseasonable cold. Places like Savannah, Georgia are expected to several inches of snow as the winter storm moves up into the mid-Atlantic coast and then delivers a wallop—and a bomb cyclone—to the northeast.

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A “bomb cyclone, or bombogenesis, “occurs when a midlatitude cyclone rapidly intensifies” when “a cold air mass collides with a warm air mass,” according to the National Oceanic and Atmospheric Administration.

What’s Coming After Thursday

Behind this powerful snowstorm on Thursday, will be a wall of cold air. AccuWeather meteorologist Renee Duff describes it as the “harshest wave of cold so far this season,” which will push into the northeastern and midwestern regions of the United States by the weekend.

Yup, the cold over the weekend is going to make Wednesday seem balmy.

“After a brief moderation from the cold at midweek, more bitter cold and downright harsh air will return,” AccuWeather Meteorologist Kyle Elliott said.

What This Means For You

The air mass behind the blizzard will be about 5 to 10 degrees lower than the one that blew into the Northeast at the end of December.

People living areas in and around Indianapolis, Detroit, Cleveland, and Pittsburgh can expect high temperatures to remain in the single digits (Farenheit) on Friday. Temperatures in New York, specifically Syracuse and Buffalo, might get above zero during the day. The area from Baltimore to New York City will have high temperatures in the teens.

By Saturday, Boston could see its lowest maximum temperature ever recorded for the date. The record of 7 degree F stands from 1896, according to Accuweather. Other low temperature records—many of which have stood since the late 1800s—could also fall in cities like Baltimore, Hartford, Connecticut, New York City, and Bangor and Portland, Maine.

So-called “real feel” temperatures will be 30 degrees below zero in some parts of upstate New York, Vermont, New Hampshire, and Maine.

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