A storm system coming from the Midwest could dump more than a foot of snow on the Philadelphia area by Tuesday morning, according to the National Weather Service.

Even higher totals are forecast for New York City, where the NWS has issued a blizzard warning for what it's calling a "crippling and potentially historic" storm.

In the Philadelphia area, light snow was expected to begin falling between midnight and 5 a.m. Monday, possibly dropping 1 to 2 inches on the city and surrounding areas by the morning commute, according to the NWS forecast. That could increase to 2 to 3 inches up by Reading.

In Mercer County, snow began falling shortly after midnight while Center City had yet to see any precipitation by 1 a.m.

Many public and private school districts across the region gave notice to parents Sunday evening that early dismissal would be in effect Monday afternoon, including in Philadelphia and Cherry Hill.

The storm, predicted to be one of the winter's largest, is expected to rapidly intensify into a Nor'easter late Monday, affecting most of the Northeast region. Tuesday snow totals in Philadelphia, surrounding suburbs and South Jersey are now projected to be in the area of 14 to 18 inches, a jump from the 6 to 8 inches forecast earlier Sunday.

Snow and winds will increase through the night, lasting at least into Tuesday morning, predicts meteorologist John Bolaris, a Philly.com contributor. Snow could continue to fall through the day Tuesday, and flights through Philadelphia International Airport, as well as land travel, are likely to be affected, he predicts.

Periods of heavy snow with blowing and drifting are expected late Monday afternoon through Tuesday, with gusts up to 30 mph and visibility as low as a quarter mile, according to the NWS. Temperatures are forecast to drop into the 20s.

The National Weather Service has issued a winter storm warning for much of Southeastern Pennsylvania and South Jersey, along with parts of Delaware and Maryland. That is in effect from noon Monday through 6 p.m. Tuesday.

In Central and North Jersey, the NWS has issued a blizzard warning for the counties of Monmouth, Middlesex and Ocean.

There, 18 to 28 inches of snow is expected to pile up by Tuesday morning, and winds of 20 to 30 mph, with gusts of 50 mph, are forecast.

In parts of New York, including Manhattan, between 20 and 30 inches of snow could fall during the storm, according to the latest NWS forecast.

Contact the Breaking News Desk at 215-854-2443; BreakingNewsDesk@philly.com. Follow @phillydotcom on Twitter.