“I would pack your patience,” said Robert Sinclair Jr., of AAA New York.

The storm, forecast to dump rain along the coast and snow inland, could cause delays at northeastern airports and along busy highways. Precipitation was forecast to sweep in from the south Tuesday night into Wednesday morning and exit the region Thursday morning.

Jeff Masters, chief meteorologist for Weather Underground, said coastal cities are likely to mostly receive rain, although he cautioned Monday afternoon that meteorologists would be keeping a close eye on the rain/snow line.

“A small deviation in the track could change things dramatically,” he said.

As of Monday, the highest amount of snow was expected to fall in northeastern Pennsylvania, the Catskills of upstate New York and into Connecticut, Massachusetts, New Hampshire and Maine. Ten inches was possible in some places, forecasters said.

Officials at the three major airports in the New York City area — Kennedy, LaGuardia and Newark Liberty — were “monitoring weather forecasts carefully,” and were ready to take action if needed, said Steve Coleman, a spokesman for the Port Authority of New York and New Jersey, which operates the airports.

Sinclair noted that an estimated 41.3 million travelers were expected to hit the nation’s highways for the holiday weekend. That’s a 4.3 percent increase over last year — propelled in part by a drastic drop in gas prices. Monday’s national average price for a gallon of unleaded was $2.813 as compared to $3.275 a year ago, according to the AAA Daily Fuel Gauge Report.

Sinclair suggested travelers consider embarking on Tuesday or Thursday, instead of Wednesday, if they can.

All the major U.S. airlines were closely monitoring the situation but have not yet canceled flights or made any other changes.

American Airlines was allowing passengers flying to some Northeast cities on Wednesday to move their flights, for free, to Tuesday or Thursday. Delta Air Lines had a similar waiver for Wednesday flights to the region, but it was letting passenger only reschedule for flights on Thursday or Friday, which might be too late for many travelers.