A powerful nor’easter could bring blizzard conditions and more than a foot of snow to some parts of the Northeast, proving that winter is not done yet.

The National Weather Service issued a blizzard watch from late Monday night through Tuesday evening for New York City and parts of northern New Jersey and southern Connecticut, while winter storm warnings and watches were issued for the remainder of the Northeast.

Meteorologists said the storm could dump 12 to 18 inches of snow on New York City with wind gusts of 40 to 50 mph.

Mayor Bill de Blasio urged residents to avoid unnecessary travel and help keep the roads clear for sanitation crews and first responders.

“We’re preparing for a significant storm on Tuesday, and New Yorkers should also prepare for snow and dangerous road conditions,” de Blasio said.

Light snow is expected to begin late Monday night and intensify overnight into early Tuesday morning. The heaviest snowfall is expected Tuesday morning through the afternoon, with snowfall rates of as much as 2 to 4 inches per hour.

“This would certainly be the biggest snowstorm of the 2017 winter season in New York City,” said Faye Barthold, a weather service meteorologist based on Long Island.

Boston also could get 12 to 18 inches, with isolated amounts of up to 2 feet across northeastern Massachusetts.

In Philadelphia, crews began treating some area roadways on Sunday. The city could see 6 to 12 inches of snow. The weather service said there is a chance the snow could change over to a wintry mix or rain for a time Tuesday morning, which could limit total snowfall amounts.

Farther south, in the nation’s capital, where the National Cherry Blossom Festival is scheduled to start Wednesday, snow accumulations of 6 to 10 inches are expected.

Winter’s last hurrah arrives just a week after the region saw temperatures climb in the 60s.

(AP)