More than 7,000 flights have been canceled worldwide over the Christmas weekend and thousands more delayed, a tracking website reported on Sunday, as the highly infectious Omicron variant brings holiday hurt to millions.

Severe weather is compounding the travel chaos in the United States, with storms expected to wreak havoc on roadways in the country's west, though they brought a white Christmas weekend to Seattle and parts of California.

According to Flightaware.com, more than 2,000 flights were canceled on Sunday — including more than 570 originating from, or headed to, US airports.

More than 4,000 delays were reported.