WASHINGTON – As much of the D.C. region and the eastern United States will see a warming trend, bad travel weather is expected over much of the central U.S.
A very strong but nearly stationary frontal system will divide the warm tropical air mass from a polar continental air mass through the weekend.
Looking at this map from Thursday, you can tell the boundary of the frontal system by the great temperature divides all the way from Texas through the Ohio Valley and into portions of central New England.
This front will creep slowly to the east. As it does so, pieces of energy will develop along the front helping to generate precipitation. By Saturday morning, a surge of moisture will move in from the Gulf of Mexico ahead of the main cold front. Widespread heavy rainfall is expected from Arkansas to Ohio by early Saturday, and the National Weather Service has already issued flood watches for several states that will be affected by this rain (shown in green).
Not only will heavy rain affect this area, but the warmth of the rain will help to melt the snow pack already on the ground, which in turn will continue to create favorable conditions for flooding.
In the Deep South and Central Gulf, high levels of instability will lend to a severe weather threat for Saturday and Saturday night. And just to the north of the heavy rainfall, temperatures will be cold enough to generate some snow, sleet and freezing rain through the weekend! Multiple rounds of precipitation will continue through Sunday morning in the already advised and warned areas.
Unfortunately, the storm will affect major airports in Dallas, New York, Boston, Atlanta, St. Louis, Chicago and Detroit and all those in between.
The eastern region, including the D.C. area, will stay in the warm zone until Sunday evening, when the front will start to move east, pushing out all the warm air we collected over the weekend. Rain showers will begin in D.C. on Sunday night and continue through the first part of Monday. Behind the front, high pressure will slowly come in, but temperatures will drop through the day on Monday and end up around 40 degrees on Christmas Eve and Christmas Day.
Monday through Christmas Day is probably the most pristine time to travel, as weather will start to calm down as high pressure moves into the surround regions.
And of course, the D.C. area is expecting terrific conditions Christmas Eve and Christmas Day! Temperatures will be below normal (unfortunately), but still the Christmas Chill will be in the air.