Jack Frost is different from the majority of pre-written Delta Green scenarios because the characters are working for MAJESTIC instead of Delta Green. Without giving away spoilers, the players will be playing agents sent to assist in the investigation of some very strange weather phenomena. They will have access to a lot of manpower and resources to do their job and all would be well if it wasn’t for the layer upon layers of secrecy and agendas and counter agendas that all lead to a nice powder keg of violence and horror when the *%#@ finally hits the fan. The investigation is decent, the supernatural forces responsible are great and the intrigue/drama potential is excellent if done and paced right.
With some modifications, this could be added to or work as a jumping off point for an ongoing campaign, but will probably work better as a one-shot (which the scenario supports by providing several pre-generated character options).