Planning a trip in the eastern U.S. this holiday season?

Pack a little extra time along with the presents. You might need it if the meteorologists are right.

First, though, the positive side to the forecast: Temperatures will be mild this week, topping out near 57 degrees Fahrenheit (14 Celsius) tomorrow in New York’s Central Park, according to the NationalWeather Service. Boston may reach 60 on Christmas Day, while Philadelphia and Washington peak tomorrow at 61.

On the down side, the balmy temperatures will be arriving with heavy rain from a storm system crossing into the Ohio Valley, and the deluge will almost certainly cause a few travel problems.

About 98.6 million people will probably set out on trips of 50 miles or more between today and Jan. 4, according to AAA, largest U.S. motoring and leisure travel organization. The two weeks that mark the Christmas-New Year’s season are one of the country’s biggest times for long-distance travel, the U.S. Transportation Department said.

N.Y. Flooding

Around New York, roads that often flood will probably do so again this week, said Brian Ciemnecki, aweather service meteorologist in Upton, New York.

“Those traveling should plan to leave extra time; it’s going to take a little bit longer to get where you’re going,” Ciemnecki said.

The weather system will be pulling in high winds along with the heavy rains, and it will be drifting through some pretty heavily trafficked airspace in the eastern U.S.

“I would anticipate some impact,” said Alan Dunham, a weather service meteorologist in Taunton, Massachusetts.

All of this is coming about because a low-pressure system off the Pacific will dive deep across the U.S. and when it hits the bottom of its curve, in the South, it will head north again.

With the circulation moving in a counter-clockwise manner, the cities east of the track will be on the warm side and those to the west will have cooler readings.

Chicago Colder

Chicago’s temperatures will peak in the mid-40s today and then drift down into the high 30s tonight and tomorrow. Chillier air may mean some snow though it’s unlikely to be a lot. St. Louis has much the same forecast.

Snow and ice in Chicago is never a good thing for air traffic.

Once the holiday begins, the air will dry out in the eastern U.S. and there will be a return to chillierweather as a cold front moves in.

A large section of the U.S., from the Pacific Northwest to the Florida, has a good chance of being cooler than normal from Dec. 27 to 31, according to the U.S. Climate Prediction Center in College Park, Maryland.

California and New England may be the outliers, with above- normal temperatures. Alaska is also expected to remain warmer than average.

Topics USA New York