A 'cold-weather bomb' is bearing down on the East Coast - and it could deliver lots of snow and record-low temperatures
- A winter storm is expected to slam the East Coast this week, bringing snow and freezing weather from Florida to Maine.
- The storm's central pressure is expected to drop below 950 millibars, which is equivalent to a category 3 hurricane.
- After the storm, the region will be slapped with an Arctic air mass on Saturday, plunging temperatures to below zero in New York City.
The East Coast will probably get even more frigid before the end of this cold snap, at least if current weather models hold true.
A "cold-weather bomb" is bearing down on the East Coast, and it could bring heavy snowfall and record-breaking freezing temperatures. Winter storm warnings have been issued from Florida up to Maine, though the specific impacts depend on which way the storm tracks. As of now, it's looking pretty daunting for the Northeast.
What is a 'weather bomb'?
This isn't hyperbole - a "weather bomb," or "bombogenesis," is the term used by meteorologists for this kind of storm system. The phenomenon gets this ominous label when the central pressure of a low-pressure system drops at least 24 millibars (a unit for measuring atmospheric pressure) within 24 hours. Bombogenesis occurs when cold, continental air masses meet warm, moisture-rich oceanic air. That can create high winds and heavy precipitation, according to The Weather Channel.
The storm working its way up the East Coast is expected to exceed the standard bombogenesis rate by several more millibars, and hit a minimum air pressure of 950 millibars - equivalent to a category 3 hurricane. Since air pressure is considered by meteorologists to be a measure of a storm's intensity, this could be one of the strongest winter storms ever to hit the East Coast (at least since records were kept). Hurricane Sandy, which devastated New York City and the New Jersey coast, had a minimum pressure of 946 millibars when it made landfall in 2012.
This GIF shows the projected pressure lows off the coast of New York and New England on Thursday afternoon, based on current models from the interactive forecast site Windy:
Current models show the storm creeping up the East Coast, bringing high winds, heavy snowfall, and the potential for coastal flooding. It's expected to dump three inches of snow on Myrtle Beach, South Carolina on Tuesday evening, a phenomenon not seen since 2010. Even Jacksonville, Florida is expected to see some snowfall on Wednesday.
By Thursday, if the storm track holds, a combination of heavy snowfall and high winds will create blizzard conditions with the potential to dump over a foot of snow in much of Southern New England, Virginia, Delaware, and Maryland, according to Mashable's Andrew Freedman. People as far southwest as Dallas, Texas, won't see temperatures above freezing for the next few days.
This shows the projected wind circulation at the same time on Thursday afternoon:
After the snow, a deep freeze
New Yorkers - who just lived through one of the most frigid New Year's Eves of the past century - may also see blizzard-like conditions if the storm shifts approximately 50 miles to the west. On its current course, New York is set to receive 2 to 4 inches of snow on Wednesday night and Thursday morning, according to the National Weather Service.
Following the storm, temperatures are expected to plunge precipitously. An Arctic air mass sitting over Canada's Hudson Bay will creep south, drawn in by the massive air circulation in the storm's wake. That could bring temperatures in New York City to the single digits this weekend, with the potential to drop well below zero Fahrenheit on Saturday evening.
Though it may seem counterintuitive, New Yorkers should hope for heavy snowfall. Gary Szatkowski, a meteorologist, explained on Twitter that even a couple inches of snow can serve as infrastructure insulation, protecting water pipes and subway tracks from extreme cold. Without that snow, water pipes can freeze or burst, which could then knock out power, creating a cascade of damage that would make commutes (not to mention life in general) a bit miserable.
Despite what President Donald Trump has claimed on Twitter, winter storms can actually be made more severe by climate change, the same as hurricanes and heat waves. As the White House and Congress gear up to take on infrastructure this year, that's probably a threat they should keep in mind.