SAN FRANCISCO (KPIX 5) — The weather is expected to worsen this week just as holiday travel ramps up at San Francisco International Airport, meaning potential trouble for travelers flying into and out of the Bay Area.

As of Sunday night, there were 400 delays and a total of 13 cancellations of flights at SFO, an airport spokesperson told KPIX. More problems could arise later in the week as wet weather looks set to return in the form of a rainstorm, just in time for Christmas on Wednesday.

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“When we got on the plane, they told us we were going to be delayed for an hour because they said that there was only one runway open,” said Wendy Underwood of Modesto.

Underwood said she luckily landed in the Bay Area on time from Chicago despite the delay. Seasoned travelers at the airport are used to seeing chaos around the hectic holidays.

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“I give myself plenty of time. I fly out of San Francisco fairly often, to LA, Dulles and even Palm Springs, so I know what’s going to happen here,” said Shane Perez of Antioch.

But passengers who spoke to KPIX seemed to take the delays in stride.

“Just wait it out, I guess. Not much you can do,” said Kurt Peek of San Francisco.

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The Transportation Security Administration says it expects to screen a record number of travelers this holiday season, yet another reason why plane passengers should allow extra travel time in their itineraries.