A massive "bombogenesis" -- an area of rapidly declining low pressure -- will wreak havoc on the Northeast this week, threatening hurricane-force winter wind gusts and blinding snow.
The bombogenesis will result in what's known as a "bomb cyclone." And the bomb cyclone, expected to strike Thursday, will likely dump 6 to 12 inches of snow in New England and hurl 40- to 60-mph gusts.
By the end of this week, parts of the Northeast will be colder than Mars.
At Mount Washington Observatory in New Hampshire, the temperature will plunge to minus 35 degrees Friday night into Saturday, weather observer Taylor Regan said. At last check several days ago, the high temperature on Mars was minus 2 degrees Fahrenheit.
But it's not just New England suffering winter's wrath. Freezing rain, sleet and snow are smothering parts of the Southeast on Wednesday.
Florida gets walloped with snow
From Maine to Florida, every East Coast state has at least one weather advisory, winter storm watch, winter storm warning or blizzard warning. That's 1,500 miles of severe weather alerts.
In Tallahassee, Florida, Ernst Beliard said he's never seen snow in his 21 years there.
"Yo its actually snowing in Tallahassee," he tweeted.
Indeed, Tallahassee had not seen measurable snowfall since 1989, CNN meteorologist Michael Guy said.
They also forced the temporary closures of Orlando water parks and prompted authorities to open dozens of emergency shelters.
Deep freeze across South Carolina
In the Palmetto State, palm trees will likely be covered in ice and snow -- and could knock down power lines, the National Weather Service in Charleston said.
"Forecasters expect below freezing temperatures to last for much of the week throughout the entire state," South Carolina Emergency Management said.
Charleston is slated to get 4 inches of snow late Wednesday. That would be the most in one day since 1989, CNN meteorologist Brandon Miller said.
Authorities urged people to stay off the streets as 1,000 snow plows and salt trucks treated roads and bridges, the state's department of transportation said.
State of emergency in Georgia
Georgia Gov. Nathan Deal issued a state of emergency Tuesday for 28 coastal counties ahead of the storm.
Savannah/Hilton Head International Airport -- typically booming with tourists this time of year -- closed Wednesday "due to severe winter weather conditions," the airport said.
But the entire state is suffering bitter conditions. In the south-central city of Tifton, Matthew Stuart Reid shot drone footage of the snowfall, set to the music of "Winter Wonderland."
At least 12 people in the US have died this week in cold-related deaths, officials said.
Six deaths were reported in Wisconsin, four in Texas, one in North Dakota and one in Missouri.
The Texas deaths included two homeless people in Houston who were exposed to freezing conditions, Houston Police Chief Art Acevedo tweeted.
Bone-chilling cold, intense snow in Northeast
New York City hasn't warmed up above freezing since Christmas -- and the deep freeze will just get worse.
The bombogenesis will usher in another round of single-digit or sub-zero temperatures to the Northeast.
New York City and Philadelphia will dip to 3 degrees this weekend, Miller said. Boston will plunge to minus 7.
And with 4-6 inches of snowfall expected in New York, sanitation workers are getting ready to deploy 2,200 plows to help clear the streets.
That snow, combined with "exceptionally strong winds," means crews will be working in near-whiteout conditions, New York City Sanitation Commissioner Kathryn Garcia said.
But despite the extreme cold in the eastern US, there have been more record highs set (381) than record lows (353) over the past week, Miller said.
Some of the cities breaking record-high temps include Los Angeles (85 degrees last Friday) and Fort Collins, Colorado (68 degrees last Friday).
Temps will drop to 3 degrees in NYC and minus 7 degrees in Boston
12 people have died from the cold, officials in four states say