You wake from your cryo sleep in a run down cryo facility built underground. You were placed there when the alarms sounded. Bombers were coming, and nuclear war may have started, but you will be awakened when it was safe for you to leave the tunnels. It would be days at most, they said, as the US's defense systems were second to none. Judging by the clock on the chamber's control panel, that was over five hundred years ago.
The facility's power systems were wearing out after so long, and it needed to wake a few sleepers every decade or so to keep from running out of power. You can't stay here, though. The atmospheric sensors are registering dangerous levels of Carbon Monoxide, and the oxygen percentage is too low to sustain us for long. If we aren't out of the facility soon, we will suffocate.
All you have with you is a forearm mounted computer which can wirelessly connect to the station's library computer from miles away (assuming your battery isn't dead), and a jumpsuit, plus whatever you can salvage before you can no longer breath. Once on the surface, we'll have to salvage for what we among the ruins and try to stay alive.