Flight delays and cancellations have picked up significantly at Denver International Airport, even as another foot of snow is expected to blanket the metropolis this afternoon.

As of 9 a.m., 806 incoming and outgoing flights have been cancelled at the airport, though only 61 flights have been delayed, according to flight tracking website, Flightaware.com.

TSA checkpoint security lines waits were still less than 10 minutes, likely the result of reduced passenger traffic because of cancelled flights.

The National Weather Service out of Boulder said metro Denver will see between 6 and 12 inches of snow, and up to 26 inches more for the foothills.

Major airlines, including United and Southwest, have been preparing for today’s delays and cancellations, allowing passengers to change their flight without cost.

The airport just kicked off spring break, one of its busiest travel seasons, and announced Tuesday the period could be record-breaking this year. More than 1.2 million passengers are expected to go through security between March 12 and 30, the airport said, up 6.7% from the same time last year.

The airport saw a strong demand for flights both in and out of Denver with Coloradans going out of town and last-minute ski tourists coming in for spring break, DIA said.

The airport had projected nearly 62,000 passengers going through security on Wednesday and 72,000 Thursday, DIA told The Denver Gazette. The busiest days will be March 16, 17 and 22, which could see more than 80,000 travelers per day.

Southwest Airlines posted a travel advisory for flights to and from Denver, Colorado Springs and Steamboat Springs, saying travelers with flights scheduled between Wednesday and Friday can change their flight within 14 days from the original flight time at no extra cost, according to the airline.

“Our operational planning teams are developing plans with a safety-focus lens to provide the best possible service to our customers in Colorado, while also protecting the integrity of our vast network during this busy spring break travel week,” Southwest spokesman Chris Perry earlier said.

United also allowed passengers to rebook flights scheduled for Wednesday and Thursday. Customers have already taken advantage of the no-fee change and passenger count for Thursday is down 30% than normal, United spokesman Russell Carlton told The Denver Gazette on Wednesday morning.