A winter storm that has tracked from the Great Plains to the Northeast has brought close to 20 inches of snow to Chicago and now threatens New York City with a significant ice event.

The “Super Bowl Blizzard” brought whiteout conditions to parts of the Chicagoland area starting Sunday morning. Visibility at O’Hare International dropped to a half-mile or less at 5 a.m., and those conditions persisted until 9 p.m. Around 5 p.m., just as football fans would have been on their way to Super Bowl parties, visibility in Chicago fell to 0.13 miles, with heavy snow and wind gusts around 35 mph.

Photo gallery: Blizzard hits Midwest

The weekend storm brought 19.3 inches of snow to Chicago O’Hare, and now ranks as the fifth-snowiest storm on record for the location. The snowiest storm on record for Chicago was the “Big Snow” of 1967, when 23 inches fell in the city on Jan. 26-27.

Sunday also goes down in the record books as the snowiest February day in Chicago — 16.2 inches fell on Sunday alone.

With 16.7 inches, the Super Bowl storm is now the third-snowiest on record for Detroit.

The storm tracked east overnight and is now targeting the Northeast with heavy rain from Richmond to Philadelphia, and heavy snow and freezing rain from New York City to Maine. Winter storm warnings are in effect across the region.

Now, with temperatures dropping below what was expected, freezing rain is the greatest threat to the New York City area. In a morning forecast update, the National Weather Service warned of “significant icing” from northern New Jersey to Long Island through Monday evening.

Despite earlier forecasts of just a trace of ice accumulation, the National Weather Service has increased the forecast to a quarter to a third of an inch of ice from freezing rain alone, and a flash freeze is expected as temperatures fall into the teens across the region this evening. The Weather Service in New York City has issued a special weather statement for the ice threat:

Anyone in the New York City area should use an abundance of caution if they’re planning on being out tonight, as streets and sidewalks could resemble ice rinks.

Boston, which is only just digging out from the 30 inches of snow it received in last week’s blizzard, is now set to accumulate another 10 to 14 inches on Monday. As of 9 a.m., Logan Airport totaled an additional 3.6 inches, while locations to the west have seen as much as 8 inches so far.

In statements on Monday morning, the Storm Prediction Center warned of snowfall rates of one to two inches per hour in eastern Massachusetts, Connecticut, Rhode Island and southern Maine. Rates of one inch per hour are expected to continue through the afternoon in northern New England.