"The coldest air in the Northern Hemisphere right now is in Canada and that's what's coming", said Rob Carolan, owner of Hometown Forecast Services.
Friday still has the 60% chance of showers before 3pm with cloudy skies expected otherwise.
Some areas may experience temperatures 25 degrees below.
If relatives and friends from out of town suddenly show up at your door, it's probably because this could be the coldest Thanksgiving period on record for the Northeast.
As of this writing, the projected high for Thanksgiving Day 2018 is 27 degrees.
According to Accuweather senior meteorologist Alex Sosnowski, most of the coldest Thanksgiving's have "occurred during the mid-1800s to near the turn of the 20th century".
Wind chills are projected to be between 6 and 12 degrees between 8 a.m. and 12 p.m. Thursday and will not improve much later on in the day. In Boston, the forecast high is 22.
That said, howling winds are also said to be on the way and - should they reach 35mph - there is a chance that larger balloons will not be allowed to fly. It will be sunny and dry on turkey day. Snow is likely to start accumulating in Pennsylvania and slowly make its way across the New England area this week, dropping up to 3 inches, though Accuweather says the Catskills of NY and coastal ME will be hit the hardest with up to six inches.
The mountains of Summit County and the Winter Park/Estes Park area will also see accumulating snow but amounts should be less compared to farther west.
Behind the snow, an Arctic blast sweeps into the Northeast late Wednesday, bringing record-cold wind chills in time for Thanksgiving.