Sarah Cohen has a plan for making the journey to her family’s big Thanksgiving get-together in Yarmouth as smooth as possible today — even as a storm bears down on the Northeast.

She, her husband, Adam, and their infant son are flying non-stop between Baltimore and Portland; Ethan’s baby’s car seat will not be checked as luggage and, therefore, won’t be lost; and they should be at the security gate two-and-a-half hours before their scheduled departure.

Because things could go awry despite her precautions, Cohen will bring her most important travel asset: An attitude that lets her accept the unexpected.

“I have learned, when something happens, you kind of have to laugh it off,” Cohen, a risk management director for a human resources firm, said Tuesday.

Other Thanksgiving travelers may do well to adopt Cohen’s attitude. Bad weather could further complicate people’s plans for one of the busiest travel periods of the year.

The forecast called for a storm to enter Maine early this morning and for snow pretty much all over the state by daybreak, according to the National Weather Service. Portland and the Midcoast can expect a total of 3 to 6 inches of snow, along with sleet and rain, until about 6 p.m. A band that includes Fryeburg, Lewiston, Augusta and Bangor may get 8 to 12 inches, while Jackman, Eustis and the extreme north is likely to get 4 to 8 inches. The southernmost part of York County may end up with just rain, or perhaps a few snowflakes.

“Unfortunately, it does not look like a very good day to travel … not around Maine at least,” said Margaret Curtis, a weather service meteorologist in Gray.

The good news is that the weather should clear up for Thanksgiving Day.

The amount of travel originating in New England is expected to increase 3.8 percent this Thanksgiving season, according to an American Automobile Association forecast. An estimated 1.79 million people – or 12 percent of the region’s population – will make trips of at least 50 miles from home. Car trips will account for 1.56 million of the trips. Air travel makes up most of the remainder.

Rising gas prices aren’t expected to significantly affect travel, according to AAA. On Tuesday, the average price for unleaded gas was $3.42 per gallon, up from $3.03 a year ago, according to MaineGasPrices.com.

A Portland International Jetport spokesman was optimistic about air travel today, despite the weather forecast.

“We’re going to get through (Wednesday) OK,” Greg Hughes said. He noted that most delays and cancellations at the jetport arise from problems at airports farther south, not because of weather in Portland.

It was a problem with an airplane, rather than weather, that derailed the travel plans of Darlene and Bill Hawksley on Tuesday. The Readfield couple’s flight was canceled, so they decided to head to Boston to get south of the storm. They expected to fly out today and land in Richmond, Va., near their daughter’s home, about 24 hours later than originally planned.

“It just cut our cooking time. We were going to make pies,” Darlene Hawksley said.

The Amtrak Downeaster is seeing heavy bookings around the holiday. Ridership has increased each Thanksgiving season for most of the past several years.

Ridership is expected to exceed 2,000 today and Friday, compared with the average daily ridership of 1,100, according to Patricia Quinn, executive director of the Northern New England Passenger Rail Authority.

“We’ve got a good crew. We’re ready for it. So bring it on,” she said.

Traffic on the Maine Turnpike can be expected to increase, though not to the levels seen on the busiest holiday weekends.

Last year, some 247,000 vehicles went through the York toll plaza between the Wednesday before Thanksgiving and the Sunday following.

That compares to 192,000 vehicles for the week prior to last Thanksgiving. Over the Labor Day weekend this year, there were 303,000 vehicles.

Cohen and her immediate family are among a number of relatives who will be making their way toward the Yarmouth home of her parent’s, Carole and Joe Long. If they all make it, 13 adults and two infants will be at Thanksgiving — a gathering known for its abundant Champagne toasts, games, football viewing, movie watching and trips to L.L. Bean.

Michelle Crimins, a psychologist married to Cohen’s cousin, Fred, was hoping to be on the road by 6:30 a.m. — right after feeding their month-old son, Alex. The Crimins, who live in New York City, would ordinarily fly to Maine but decided against doing that with a newborn.

They’re planning to break up their trip into two legs, stopping at Fred’s parents home in Boxborough, Mass., overnight and continuing to Yarmouth on Thursday.

Still, she’s a little nervous. It’s the baby’s second car trip — the first being for a doctor’s visit 20 blocks away — and there’s also the traffic and weather. She’s been monitoring the forecasts for New York, Boxborough and Portland through an app on her phone.

“These are things you do around the holidays for family,” she said. “We’re doing it with a full heart.”