My Traverse has moisture build up on the inside of the windshield if it rains for a couple days in a row. If the weather is is cold the moisture forms ice on the inside of the windshield and has to be scrapped off.
Could be the AC drain is blocked and not draining. The drain in usually under the hood, on passenger side of the firewall. Sometimes can be cleaned out just using your finger or a small bottle brush might be required.