Two meters is where most of our communications takes place and that happens between 144 MHz and 148 MHz. And, when the chase team is out hunting down a balloon they use 70 centimeters which is between 440 MHz and 450 MHz. Just about all scanners cover these frequencies, but, ask your dealer to be sure the scanner you are looking at will pick them up. One final word here on monitoring. If you can see the front range of Colorado you probably need no more than the little antenna that comes with the scanner.
Hams talk through something called repeaters.
That is, they transmit to remote automated stations on mountain tops, where their signal is retransmitted. For us in Colorado, we have the ideal environment for this. Many repeaters are located at and even above the 10,000 foot level. People back east would KILL for that transmitter height. You will often be able to hear the Chase teams all over eastern Colorado.