Bad weather is challenging the U.S. air travel system early this week with severe thunderstorms and tornado warnings forecast from New England to the Carolinas amid a partial government shutdown.

A severe weather front has dumped heavy snow on the Upper Midwest, caused thunderstorms in the South and threatens Mid-Atlantic states with rain and possible tornadoes.

A nor'easter is forecast for the East Coast this weekend, but the amount of snow that falls − and where − remains challenging to pinpoint as of Friday Feb. 20.

Start making new travel plans. Thousands of flights have been canceled due to severe storms. Here's where, as well as which airlines and airports.

From a surprising heatwave in California to blizzards burying parts of the Midwest and storms rolling over the East Coast, chaotic weather ut more than half the nation's population in the path of extreme conditions.

People all along the East Coast — including in Pennsylvania — are battening down the hatches as extreme weather hits the region. Needless to say, if you’re supposed to catch a flight some time today,

Temperatures in some places plunged as much as 40 to 50 degrees in 24 hours. On Wednesday, Washington, D.C., hit 86 degrees, shattering a same-day record of 79. Even at 5 a.m. Thursday morning, it was 75 degrees.

Chaotic weather, from surprising heat in California to the threat of storms rolling into the East Coast, put over half the U.S. population in the path of extreme conditions Monday.