The
National Weather Service is forecasting a rapidly deepening area of low pressure just off the East Coast of Florida will move northeastward to the Canadian Maritimes by Friday. The storm will produce areas of snow and rain/freezing rain along the Southeast Coast through last Wednesday evening.
As the storm begins moving up the East Coast, rain will develop over parts of the Southern Mid-Atlantic Coast that will change over to all snow by Thursday morning. Snowfall is expected to be heavy at times. By early Thursday morning, the snow will begin developing over parts of New England, again, resulting in heavy snowfall at times and continuing through Friday.
Meanwhile, a front over the Great Lakes extending into the Middle Mississippi Valley, then extending northwestward into the Northern High Plains and move into the Lower Great Lakes/Ohio Valley to the Lower Mississippi Valley by Wednesday evening. This low-pressure system will end up being absorbed into the greater circulation of the deepening coastal storm by Thursday morning.
Forecast record cold high temperatures on Friday, Jan. 5, 2018. Broken records indicated by circles.
NWS
A 'bombogenesis' in the making
Meteorologists are doubly concerned because this storm is a mid-latitude cyclone that is rapidly intensifying. As
NOAA explains: "If this storm rapidly intensifies, dropping at least 24 millibars over 24 hours, we would experience what is known as a weather 'bomb,' for a process called "bombogenesis."
"A minimum central air pressure of below 950 millibars would be an unprecedented intensity for a non-tropical storm in the Northeast during the past 30 years," said to Anthony Sagliani, a meteorologist at Earth Networks, according to
Mashable.
It snowed in Tallahassee, Florida this morning. This video was Tweeted by Mike Seidell with the Weather Channel.
In general, the lower the air pressure, the stronger the storm. That is why hurricane forecasts include "minimum central pressure" readings. Computer projection models show this storm could easily reach a peak intensity that is rarely seen off the East Coast. A minimum central pressure reading of 950 millibars is equal to a Category 3 hurricane.
The storm's development has a lot to do with the
frigid air mass already in place over a major portion of the U.S. and the unusually warm Gulf Stream waters in the Atlantic.
"Relationships between the ocean and atmosphere are complicated, especially as they relate to explosively developing extratropical cyclones (like the one currently in the forecast)," said Daniel Swain, a climate scientist at UCLA, in a Twitter message.
"But the extreme thermal contrast between very cold atmospheric temperatures over land and an unusually warm nearby Gulf Stream certainly sets the stage for impressive storm-strengthening potential," he said.
"Ocean conditions are not the only factor at play (atmospheric conditions, like the position and strength of jet stream winds in the upper atmosphere, are also critical), but they’re definitely important."
Track of the storm into Canadian Maritimes
This could be a storm for the record books as Nove Scotia, Canada will take a direct hit — causing power outages from hurricane force winds, along with heavy snow, heavy rain, and battering waves. It is going to be a crippling storm no matter how we look at it.
The problem is this — the heart of cold air over North America and parts of the Arctic is currently parked over Hudson Bay, Canada. And the enormous circulation associated with the current storm is expected to drag more frigid air down into the U.S., causing more extreme conditions for the Midwest and East Coast.
We needn't worry about breaking any daily temperature records over the next few days because most all of the cold records will be broken through Saturday and possibly into next week. And forecasters are warning that even without snow, homeowners need to worry about frozen pipes and other infrastructure.
And it also goes without saying — the bitterly cold weather is dangerous and heavy winds and freezing temperatures are a lead-in to a case of frostbite. So be careful.
