The weather did not help the situation; the rain and cloud cover forced the airport to switch to its ground delay program at 8:30 a.m. That means planes can't land simultaneously but rather single file, triggering flight delays.
SFO officials recommend you add a little extra time to your getaway plan today in case you get stuck in some long slow lines. The airport says there will be about 50,000 more people at SFO today compared to a regular day.
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"My luggage was 45 pounds and it's only allowed to be 33 pounds. So I needed to open my luggage six times -- but I did it," said Carolina Monroy, who was headed to Mexico City.
The Knight family from Alameda was caught off guard by the crowds this morning.
"We are going to throw some tags on our bags here and run for the gate. I don't think we are going to wait in this line. We are concerned we are not going make it," said Spencer Knight.
All of this is why Daniel Rodriguez gave himself some extra time.
"We got here a little earlier, about an hour earlier. We knew the lines were going to be all over the place. I am excited to get home finally," he said.
AAA is expecting this to be a record year of travel because of the strong economy. An estimated 6.7 million people are predicted to travel by plane this year, a 15-year high.
While it is very busy at SFO, airport officials say it is not the busiest day of the year -- that day usually comes around 4th of July weekend.
Check drive times and traffic maps before heading out the door.
Check out the long security line at terminal two in the San Francisco airport. Today is expected to be the busiest travel day of the Christmas holiday. pic.twitter.com/1HLMsILD3P— Amy Hollyfield (@amyhollyfield) December 21, 2018