Blizzard At Millenium Park in Chicago, Illinois
A woman walks up a hill in Millennium Park during blizzard conditions in Chicago, Illinois, February 1, 2015. REeuters/Jim Young

Air travel in the United States has taken a hit as multiple winter storom warnings have been issued on Sunday. A winter storm is reportedly ramping up in the Great Plains.

CNN reports that more than nine million people from the metropolitan Chicago area are affected while 65 million more are under a winter storm warning across 18 states. Chicago is expected to get as thick as 15 inches of snow. Chicago Mayor Rahm Emanuel said at a press conference on Sunday, the streets will stay ploughed and passable while the people will be safe and secure. According to officials, more than 350 pieces of equipment, which included salt spreaders and plows, were fanned out across Chicago.

More than 2,000 U.S. flights have been cancelled on Sunday. Many of those flights were supposed to fly in and out of Chicago.

According to CNN meteorologist Michael Guy, rain is going to pose additional problems. "Rain will be the problem across the southern portions of this storm system, with a possibility of scattered storms from east Texas to Mississippi Sunday as the storm moves east," he said.

The Weather Channel reports the most intense period of snow in the Midwest is expected to hit right around game time for the Super Bowl. This means the storm may make it unsafe for people due to hazardous road conditions. Drivers may face snarling snow drifts and terrible visibility as it is expected that there will be wind gusts of up to 40 mph.

Michigan, Wisconsin, Illinois and Iowa may experience up to a foot of snow. There are still multiple winter storm warnings to the Plains from South Dakota and eastern Nebraska. The storm will reportedly move east to affect key metropolitan areas like Boston and New York City on Monday.

"New York City could see a wintry mix of precipitation just in time for the morning commute with a possibility of sleet and ice," Guy said. He added Boston would "get another round of wintery weather with new snow accumulations from 10 to 12 inches."

National Weather Service meteorologist Gino Izzi said that ground zero would be in the heart of Chicago. He said road conditions were not expected to improve even later on Sunday.