Jan. 31 --
A powerful nor'easter was taking shape along the mid-Atlantic coast Sunday with forecasters warning residents to "buckle up" as the developing winter storm will be a long-duration event for some areas and unload up to 36 inches as it lashes parts of the Northeast into the middle of the week.
Winter storm warnings and winter weather advisories were in effect across the Northeast as snow and ice began breaking out across the region Sunday.
Philadelphia Managing Director Tumar Alexander announced a snow emergency will be in effect from 6 p.m. to Tuesday in preparation for the nor'easter snow event that is forecast to bring upward of 12 inches of to the city.
More than 400 pieces of snow equipment from the city and contractors will be on the streets by Sunday night while the Streets Department has made 50,000 tons of salt available, the city said.
In New Jersey, Gov. Phil Murphy declared a state of emergency starting at 7 p.m.
"State agencies are ready to respond, and we will use every resource at our disposal to ensure the safety of New Jerseyans," he tweeted.
All six so-called mega vaccine sites will be closed on Monday and all New Jersey transit buses, rail, light rail and Access Link services will be suspended for the day, he said.
The New Jersey Department of Transportation is urging the public to stay home and off the roads.
In New York City, Mayor Bill de Blasio Monday night also declared a state of emergency from 6 a.m. Monday, restricting non-essential travel into the city.
"This winter storm will be dangerous with heavy snowfall and strong winds," he tweeted. "If you can stay home, stay home. Keep the roads clear for emergency vehicles."
Code Blue was also put into effect, which is issued when the temperature drops to 32 degrees Fahrenheit or lower, offering shelter to all those without homes.
Ahead of the snow beginning to fly, the school district announced all buildings will be closed on Monday and classes will be held remotely.
After-school programs, adult education, food distribution sites and other programs have also been canceled.
In Washington, D.C., Mayor Muriel Bowser announced that classes in the nation's capital would also be held virtually on Monday and that all public COVID-19 testing sites will be closed but the D.C. government will remain open.
"Please contact your doctor if you're experiencing [coronavirus] symptoms and stay home," she tweeted.
In Virginia, four firefighters were taken to the hospital for minor injuries after a Henrico County fire truck overturned on a call Sunday morning due to snowy road conditions.
Officials said the truck spun off the paved roadway and overturned, but no other vehicles were involved in the accident.
AccuWeather meteorologists have been warning for days that as a winter storm presses into Ohio late in the weekend, a secondary storm will take shape and become a full-blown nor'easter along the Eastern Seaboard.
The process began Sunday afternoon, and heavy precipitation was developing across the mid-Atlantic into a nor'easter, which is a large storm that spawns northeasterly winds along the East Coast of the United States.
"As a storm shifting through the Ohio Valley slowly moves east, a secondary storm will take shape along the Carolina coast later Sunday," explained AccuWeather Senior Meteorologist Danny Pydynowski.
"The coastal storm will then become the dominant storm of the two, strengthening into a full-blown nor'easter along the Atlantic coast."
As the two storms interact with one another, a broad area of snow will expand from the Ohio Valley through the Northeast.
"The two storms will pull a lot of moisture from the Atlantic across the region. With Arctic air still in place, this will lead to a broad swath of accumulating snow that will persist for days," explained AccuWeather Meteorologist Brett Rossio.
Some locations in the Ohio Valley and central Appalachians, where snow created slippery travel on Sunday, can expect rounds of snow to last all the way into Monday night. In much of the mid-Atlantic, the storm is forecast to extend from Sunday to Tuesday. Parts of New England will face storm impacts from Monday to early Wednesday.
"This will allow for snowfall totals to really build up over large areas of the Northeast," Rossio explained. A large area of 6-12 inches of snow will stretch all the way from Ohio through the central Appalachians into New England.
"Even though the forecast is for nearly a foot of snow in some of these interior areas, it could be a little misleading in terms of what impacts to expect," AccuWeather Senior Meteorologist Kerry Schwindenhammer said. "With the gradual nature of the accumulation in many of these areas, clean-up crews may be able to 'keep up' in a relative sense."
However, closer to the coast, forecasters warn it will be a much different story. "It will be very different near the coast," as this region is expected to get hammered by the heaviest snowfall, Schwindenhammer said.
Pydynowski compared the predicted storm impacts for inland areas to coastal locations to the fable of The Hare and the Tortoise.
"Many areas farther inland will be like the tortoise, slowly but steadily building up impressive snowfall totals. Coastal areas will be like the hare, with impressive snowfall totals piling up very quickly. We'll see who ultimately wins the race and sees the highest report."
Accuweather meteorologists expect widespread snowfall totals of 12-18 inches where the heaviest snow falls. A bulls' eye of nearly 2 feet could target a small area just north and west of New York City, into the Pocono and Catskill mountains, with an AccuWeather Local StormMax&trade of 36 inches.
The densely populated Interstate 95 corridor in the Northeast will be in the thick of the winter storm. Sunday morning snow was already spreading across the nation's capital, with slushy roads and slippery travel developing. Forecasters warn that in these areas, snow could become heavy and pile up very quickly.
Snow will continue to gradually spread northeastward through the mid-Atlantic and New England Sunday and Sunday night.
"Snow is expected to arrive in New York City this afternoon, but may take until after midnight until it really becomes steady," Pydynowski said. "Boston will start to get in on the action later Monday morning."
Snowfall rates will be much heavier near the coast, closer to the center of the powerful nor'easter. Snowfall rates could reach 1-2 inches per hour along the I-95 corridor from New Jersey through New England. There could also even be the chance for some thundersnow.
AccuWeather meteorologists expect New York City to see a major snowfall from this event, somewhere in the 10- to 15-inch range is likely. Boston will also see significant snowfall from the storm, about 6-12 inches, even if there is some mixing for a brief time.
Some milder air higher in the atmosphere could cause precipitation to change to a wintry mix, including sleet, then perhaps rain near the coast. This scenario is most likely near Cape Cod as well as along the southern mid-Atlantic coast.
"Much of the Jersey Shore, Long Island and New England coast should remain just cold enough at all levels of the atmosphere to stay all snow through the storm," Rossio said.
Farther south, more mild air will mix in as well, keeping snowfall totals a bit lower in places looking to erase a long-lasting snow drought.
In Philadelphia, a similar situation could unfold, although enough cold air is likely to hold on to result in more snow.
"At least a few inches of snow is likely in the Philadelphia area Sunday afternoon and evening, before changing to a mix of sleet and perhaps some plain rain and drizzle for a time late Sunday night," explained AccuWeather Senior Meteorologist John Feerick
"However, it will change back to all snow late Monday morning or midday with a few more inches likely to come after that. There is a chance it could stay all snow through Sunday night, resulting in higher snowfall amounts."
Along with the significant snowfall, powerful winds will develop near the coast. Wind gusts of 30-50 mph, with an AccuWeather Local StormMax&trade of 65 mph, will create blizzard conditions at times. Travel in areas from Trenton to New York City to Boston could become nearly impossible during the height of the storm from later Sunday night into Monday night.
The strong winds blowing onshore will also lead to some coastal flooding and beach erosion from the rough surf it will generate. Localized power outages will also be possible where the strongest gusts occur from any downed tree limbs or power lines.
As the storm reaches peak strength Tuesday just off of the New England coast, the heaviest snow will also begin to shift off into northern New England and Atlantic Canada. However, lingering areas of light-to-moderate snow will still plague the Northeast and the wind field will also expand.
With this interior areas of the Northeast will also start to get breezier. "Much of the snow that piles up in interior areas will not be accompanied by much wind Sunday and Monday," Rossio said. "However on Tuesday, areas all the way through the mid-Atlantic into the western Ohio Valley will see a gusty breeze develop."
This will prolong impacts from the storm in these parts by creating areas of blowing snow. "Much of the snow that falls across these areas will become light and fluffy by the end of the storm, so any wind will be able to blow it around pretty easily," Rossio added.
Travel delays along major thoroughfares like Interstates 90, 81, 80, 76 and 70 could be extended through Tuesday with blowing snow recovering plowed roads in open areas. Farther east in the mid-Atlantic and Northeast, some issues with blowing snow could persist all the way into Wednesday.
"It really won't be until Thursday, when high pressure briefly moves in ahead of the next storm forming in the central U.S., until folks in the Northeast will really be able to put a wrap on this nor'easter," Rossio said.