Here's a terrifying thought. Officials now estimate that 600,000 people are coming to Wyoming this weekend. Most of them will be driving up from Colorado.

While traffic will be congested througout the weekend, Monday is expected to be even worse, especially on I-25 South from Casper to the Colorado border. Along with over 100,000 extra cars on the road, it's also the first day of classes for Colorado State Univeristy and the University of Colorado.

On a normal day, Casper is less than three hours away from the state line. There's no telling how long that drive could take on Monday.