ARLINGTON, Va. − Two powerful weather systems were careening across the nation Tuesday, threatening to dump up to a foot of snow in some areas while snarling traffic, clogging roadways, shuttering schools and shutting down government offices.

Around 2:30 p.m., some snow was showing up on weather radar in the Garden State, but a dry layer of air in the lower atmosphere was causing the snow to evaporate before reaching the ground. That’s a phenomenon known as virga. Shortly before 4 p.m., light snow was reported in parts of Cape May County, including Wildwood and Cape May.

The FOX Forecast Center is tracking the development of several winter storms that are expected to sweep across the U.S. this week, putting tens of millions of people in about 40 states on alert for snow,

Another blast of winter moves across the U.S. putting 30 million under weather alerts already - with the East Coast next to be hit - Dozens of flight cancelations and delays were already reported in Washington,