A quick but very cold blast is moving in.
East Boston resident Leigh Williams and her dog Sherwin are ready.
"He doesn't like the cold, so it will be a lot faster. Get the business done and get back inside," she said.
The Arctic cold front is expected to bring wind chills lower than minus 50 to some parts of northern New England. The strong winds and cold air will create wind chills “rarely seen in northern and eastern Maine,” according to an advisory from the National Weather Service office in Caribou, Maine.
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Jay Broccolo, director of weather operations at an observatory on New Hampshire’s Mount Washington — which for decades held the world record for the fastest wind gust — said Thursday that wind speeds could top 100 mph.
“We take safety really seriously in the higher summits, and this weekend’s forecast is looking pretty gnarly, even for our standards,” Broccolo said.
The brief, two-day blast of frigid weather is forcing the City of Boston to activate its cold weather emergency plan. All Boston Centers for Youth and Families locations throughout the city will act as warming centers during their regular hours on Friday and Saturday.
Boston Public Schools also announced Thursday afternoon that classes are canceled on Friday due to the extreme cold weather conditions. All extracurricular activities on Friday through Saturday are also canceled.
"With extreme weather conditions and many of our students commuting to and from school, walking, and waiting for public transportation outdoors, we have made the decision to close for the day," Superintendent Mary Skipper said in a statement. "Due to the low temperatures and strong wind gusts, there is an increased risk of hypothermia and frostbite. We acknowledge closing schools is a challenge to many of our families and encourage families in need to take advantage of warming centers on Friday and Saturday. We make these decisions with the best interests of our students top of mind and we want to ensure they are safe in these weather conditions.”
The cold is also expected to impact travel on Friday and Saturday.
The MBTA said it is planning to store subway trains in tunnels after the end of service Friday night to protect them against the cold and is delaying a previously scheduled Orange Line service suspension between Ruggles and North Station.
And MassDOT said it has decided against closing the Sumner Tunnel this weekend because it will be too cold to complete the work it had planned.
Flight delays are possible at Logan Airport and Worcester Regional Airport due to the extreme cold, MassDOT said. Thousands of flights have already been canceled this week in other parts of the country due to winter weather conditions.
Massachusetts Gov. Maura Healey said she will use her authority on a case-by-case basis to keep South Station in Boston open during the cold snap, on Friday night and Saturday night.
“We have been in close contact with local leaders and service providers to make sure people are being taking care of during the extreme weather, including having providers available to offer transportation to shelter for those who want it as well as other resources,” she said in a statement. “We encourage anyone who needs a place to stay to accept this offer and spend the night at a safe, warm shelter rather than at the station."
Boston Mayor Michelle Wu is also asking people to check in on those who are most vulnerable.
And if you're out and about, wear several layers of loose-fitting clothing, a hat, a scarf, and something to cover your face or any other exposed skin.
To the north in New Hampshire, Gov. Chris Sununu said at a press conference Thursday that state agencies are coordinating with cities and towns and local service providers to prepare for the arrival of the cold. Anyone in need of temporary shelter can call 2-1-1 to locate the closest site that is open and available to them. Additional resources can be found at ReadyNH.gov.
As temperatures get set to take a nose dive outside, there are also things you can do inside to prepare.
If you lose power or have poor insulation, turn on your faucet to let the water drip. It will help prevent freezing pipes. Set your thermostat to at least 65 degrees, insulate your pipes, and seal your windows.
And don't forget your car.
"You really want to make sure that you're taking the steps that you need to take to make sure your vehicle is safe," Mary Maguire of AAA Northeast told us.
That means making sure you have an emergency kit with a blanket, first aid items, a flashlight, water, snacks and jumper cables. Also make sure you have windshield washer fluid, that your tires are properly inflated, and get your car's battery checked now before the real cold moves in.
AAA says they are expecting a lot of dead battery calls this weekend.
"When temperatures dip below zero, as they're expected to on Saturday, your batter actually loses more than half of its power," Maguire said.
So how do you know if your battery is OK? Well, if it's more than five years old, experts say take it in to get tested.
The Associated Press contributed to this report.