By Pat Loeb

PHILADELPHIA (CBS) — After a day full of flight delays and cancellations on Sunday (see related story), airlines serving Philadelphia International Airport are planning how do deal with tomorrow’s forecast, which calls for more snow.

Some airlines flying into and out of Philadelphia say they are willing to help passengers who want to change their plans ahead of the storm.

The airport’s two main carriers, US Airways and American, say they will waive change fees in light of the forecast.

“People have been able to reschedule flights if they’ve been proactively planning,” notes airport spokesperson Victoria Lupica, “and the airlines, if they know that they’re going to be making any adjustments, have certainly been contacting their passengers.”

No schedule changes have been made as of noon Monday for Southwest Airlines, according to spokesman Dan Landson — but he says their passengers are always free to adjust their plans.

“We don’t charge change fees, so you can always change your flight,” he reminds travelers.

Yesterday, airlines were scrambling when the airport had to shut down runways to clear the unexpectedly heavy snow, but Lupica says passengers all were accommodated by this morning.

PHL was in a ground stop program due to low clouds from 5 p.m. until 5:45 p.m. Monday night. The ground stop has since been lifted.

The airport says to call 1-800-PHL-GATE, check their website or your airline for flight status.

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