An outbreak of severe thunderstorms that could impact millions and snarl air travel across the country is expected to unfold today and tonight across a large portion of the Ohio Valley and Northeast.
Storms with torrential rain, damaging winds and hail will be ongoing this morning from the central Great Lakes into a portion of the Northeast, before another, possibly more significant round takes shape a bit farther south this afternoon and evening.
There is the potential for a large area to experience destructive wind gusts in excess of 70 mph, enough to bring down trees, damage structures and cause power outages that could last for days.
Major metropolitan areas, including Cleveland, Pittsburgh, Philadelphia, New York City, Albany and Hartford, are among those included in the enhanced risk zone for damaging winds through tonight.
An even larger area will still be at risk for severe weather, stretching from the mid-Mississippi Valley near St. Louis and Paducah all the way east into the mid-Atlantic and north to New England.
Similar to Wednesday night's damaging storms in the Upper Midwest, many areas will actually experience their worst weather after dark, especially along the I-95 corridor from Washington, D.C., to Boston.
In addition to the threat of powerful wind gusts, the setup appears ripe for a few storms to spawn tornadoes. This will especially be the case near the leading edge of a push of warm, humid air from northern Pennsylvania and southern New York into southern New England at night.
Hail as large as golf balls and rain heavy enough to cause rapid street flooding will also accompany many storms.
Driving along even major interstates could become difficult during storms, whether it be along I-71 from Louisville to Cleveland, I-80 from Akron to New York or I-84 from Scranton to Worcester.
By the end of the night, tens of thousands of lightning strikes will have occurred from the storms. Even if you are well ahead of or behind a storm, you still face the risk of being struck by lightning.
With such a multifaceted threat faced over a wide, highly-populated area, it is important that everyone from the Ohio Valley into the Northeast stay up-to-date with the latest on the location of the storms.
A system tracking over the Rocky Mountains will spread snow over the region and into the Plains through the remainder of the week.
While lacking across a large part of the United States on Christmas Day, arctic air is set to make a comeback during the final days of 2014.
A winter storm will impact the United Kingdom and central Europe for Boxing Day and the holiday weekend.
On Christmas Day in 1776, George Washington led his troops across the Delaware River, in spite of treacherous weather, for a pivotal moment in the Revolutionary War.
While many areas across the country felt a milder Christmas morning, residents across Utah, Montana and Idaho woke to snow-covered ground in time for holiday celebrations.
While many bowl games will be played in warmer locales this year, there are others that will face cold and potentially wintry conditions in the Midwest and Northeast.
International Falls, MN (1991)
38 degrees - the "warmest" Christmas on record.
Texarkana, TX (2000)
Ice storm shut down the area. Complete power failure in the city.
The Northeast (2002)
First snowstorm to affect the region on Christmas day, since 1978. 30 inches fell in Cooperdtown NY, 21" fell in Tobyhanna, PA and 19.5 inches fell in Albany NY.