Deja vú is settling in as the third nor’easter in less than two weeks begins to slam the Northeast Monday night, packing blizzard conditions, up to two feet of snow, and more coastal flooding to portions of New England. No doubt travel will be disrupted by this storm. Over 1000 flights have been canceled so far for Tuesday, and many schools are expected to close across New England. In fact, Boston and Providence Public Schools are already closed. So the model guidance this Monday has trended the track of this nor’easter a bit to the west, or closer to the coast, which will bring highly-impactful weather and greater snowfall totals to a larger region. It has also forced the National Weather Service office in Boston to issue Blizzard Warnings from eastern Massachusetts and the islands, with the exception of Boston and Nantucket. This warning will be in effect until 8pm Tuesday.
So let’s discuss the set up with this nor’easter: the low pressure has already formed off the Carolina coast as energy phases from a weakening low pressure over the southern Appalachian Mountains to offshore. Pressures with this coastal low are at around 1000 millibars, as of Monday evening, but this storm will undergo bombogenesis, allowing for this storm to become a bomb cyclone. By Tuesday evening, the minimum central pressure of this nor’easter is expected to be down to around 970 millibars, which is equivalent to a near-category 3 hurricane. That’s about a 30 millibar drop of pressure in less than 24 hours, which would verify this storm as a bomb cyclone. Thankfully, this storm will remain far enough offshore from the Northeast so no town will receive anywhere close to the 100+ mph wind gusts, but unfortunately our friends in Canada may as it makes landfall onto the Canadian Maritimes Tuesday night.
The track of this storm remains a bit uncertain. If there are any further westward shifts, then that can bring heavier snow into the New York City area, but we are feeling pretty confident with the snowfall totals we are predicting, which you can find later on in this article. The low pressure is expected to track just southeast of the 40/70 Benchmark Tuesday morning, then will head toward the Canadian Maritimes Tuesday night. As a reminder, the benchmark often signifies how impactful a nor’easter may be. If a storm moves southeast of the benchmark, then heavy snow would typically be confined to the coast; if a nor’easter tracks northwest of 40° N, 70° W, then heavy snow would be found inland with mixing concerns at the coast.
So now let’s discuss the forecast in how you will be impacted. A trough of low pressure extending from the nor’easter will allow for the development of a light to moderate snow from Upstate New York through the Catskills and eastern Pennsylvania. Then as the storm moves up the East Coast, snow will break out before midnight from eastern North Carolina up through the Tidewater of Virginia, the DelMarVa, New Jersey, Long Island, and the southern coast of New England. Along the Mid-Atlantic coast, the precipitation may begin as rain, but then a changeover to snow is expected for a brief period. Mainly up to a slushy inch can be expected while west of there, including Washington, D.C., no snow falls. The classic D.C. snow hole strikes again! Then as we get into the early morning hours of Tuesday leading up to sunrise, the snow will expand as the low tracks to the north-northeast into most of New England while coming to an end across much of the Mid-Atlantic. Meanwhile to the north, snow will persist along a boundary from the Catskills through Upstate New York.
Tuesday will be the big day with the worst impacts, especially in southeastern New England where up to two feet of snow is forecast to accumulate. In terms of the snow, a moderate to heavy snow is forecast to fall through most or all of the day across New England and into most of New York State while lake-effect snow showers affect portions of the Great Lakes region, including western New York. From New York City through Boston in the I-95 corridor, a rough morning commute is likely, especially as you get outside of New York City, where you will encounter snowfall rates of up to two to three inches per hour. The evening commute will also be rough in New England. The snow should come to an end by the evening in and around New York City but most of New England, with the exception of the south shore, will continue to get pummeled.
There will be two distinct snow bands that are expected to develop Tuesday morning, which is quite typical with these dynamic winter storms. The models throughout the day Monday have been pretty consistent on where these two heavy bands with snowfall rates as high as two to four inches per hour will set up. There will likely be one that forms near the New York/New England border. If this band gets into New York City, then three to six inches could fall than the one to three currently forecast. The more powerful band, however, will be located across southeastern New England and into the eastern end of Long Island. This is where the jackpot snowfall totals of over a foot of snow will be found, and even thundersnow may occur. There will be intense frontogenesis or lift, as shown in the red and pink shadings on the graphic below, in this region that will lead to this heavy snow and thunder potential.
Then during the overnight hours of Tuesday, our nor’easter will slow down as it makes landfall in Canada while pressures level off and gradually rise again due to the disconnect of the relatively warm sea surface temperatures. Snow will come to an and end around midnight from Boston and areas to the south and west while snow continues to come down strong across northern New England and Upstate and western New York. Lake-effect snow is also possible along the coast of Lake Erie while enhanced lift in the Appalachians leads to move snow from West Virginia southward through Tennessee and North Carolina.
On Wednesday, our nor’easter will make a loop and will move slowly toward Maine. While the widespread snow activity will be over with for the I-95 corridor, snow is expected to persist or expand across much of the interior Northeast while snow squalls work through much of New England into the evening hours, which may drop a quick inch of snow with lowered visibilities. Then during the overnight hours of Wednesday, much of the snow will quickly dissipate, although scattered snow showers and lake-effect snow will continue into Thursday across portions of the Great Lakes region and northern New England.
So we focused on the snow but winds will also be an issue with this storm. Winds will gust up to 20-30 mph across the entire Northeast Tuesday into Wednesday. Winds will be higher toward the coast due to less friction and the closer proximity to the center of the nor’easter. Winds will gust up to 40 mph along the Mid-Atlantic coast, on Long Island, and along the southern shore of New England. Then as you get into southeastern New England, winds will gusts up to 40-50 mph and up to 45-55 mph along coastal eastern New England, peaking in intensity Tuesday afternoon and evening. The worst of the winds will be found on the islands of Massachusetts and on Cape Cod. This is the area where winds are expected to gust as high 60-80 mph. This also happens to be where the Blizzard Warnings are in effect, so the combination of heavy snow and strong winds will create impossible driving conditions at times.
Based on this wind forecast, the entire Northeast is at risk for isolated power outages while widespread outages can be expected in eastern New England, especially on the islands and Cape Cod due to the severe winds and heavy, wet snow. This can produce more power outages than the past two storms in this area.
Lastly, there is the risk for coastal flooding. Thankfully, tides will be lower than normal due to the current moon phase, so that will lower the potential for major coastal flooding. From the Delaware and New Jersey coast, then along eastern New England and on the Massachusetts islands, minor coastal flooding Tuesday morning or midday Tuesday is expected with a storm surge as high as three feet, especially along the eastern Massachusetts coast. No moderate to major flooding is anticipated with this nor’easter.
Stay with WeatherOptics throughout the extent of this nor’easter. We’ll have live storm updates from our Twitter account, which you can view here.