Missoula International Airport shut down its primary runway promptly at 1 p.m. on Tuesday to begin a $964,000 resurfacing job – including a new runway designation to reflect the airfield's true magnetic alignment.

Inside the terminal, crews took up the electrical work needed to install a third security checkpoint. The new lane, needed to accommodate the morning influx of passengers, is slated to open May 2, the day after the runway opens.

On that second day in May, Frontier Airlines will also recommence its seasonal service to Denver.

The busy season has arrived at MSO, and while airport officials are knee-deep in accelerating plans to begin constructing a new terminal, they're also working to handle the current growth in passengers.

That's expected to increase again this year, topping 400,000 travelers, and the rush will commence in June.

“June 7 is the day we flip our switch,” said Brian Ellestad, the airport's deputy director. “The numbers are going to go crazy this summer.”

While Frontier leads the way on May 2 with service to Denver, American Airlines follows suit on June 7, launching new service to both Dallas/Fort Worth and Chicago.

That same day, United Airlines also begins service to Chicago, San Francisco and Los Angeles. Just a few days later, Delta begins nonstop service to Atlanta, followed in mid May by service on Allegiant to Los Angeles and Oakland.

Handling all those passengers, not to mention aircraft parking, is a challenge airport officials are happy to tackle. A few short years from now, a new concourse will open, along with a modern security checkpoint.

But getting from here to there may require patience.

“For the month of June, we will see 26 percent more seats in our market than June of last year,” said airport director Cris Jensen. “It looks like it will be another record year, and we will likely top 400,000 enplaned passengers for the first time in our history.”

Last month, airport officials expressed concern with the time it took morning passengers to pass through security, with waits as long as 30 minutes. Some passengers missed their flights.

While adding a third checkpoint is a temporary solution, it could help move passengers through security faster as airport traffic grows.

“We've had some extended wait times in the morning,” Jensen said. “We're excited that after months of lobbying the TSA, and with some help from our congressional folks, we were able to get over the hump on that. That third lane is a big deal to us.”

Later this year, security will move to the center of the airport lobby, clearing the way for demolition of the west wing and construction of the first new concourse. That project is expected to open in late December 2021.

“It's a little intense around here right now,” Jensen said. “Our staff is a little hurried trying to make sure we're covering all the bases and making sure everything goes off without a hitch.”