How does the in-game time and the day/night cycle work

tomb-raider-2013

First time I played the Summit Forest level, it was night:

When I fast traveled to come back there later, it was day:

How does time pass in the game? What exactly determines the day/night cycle of the game? And how does the in-game time correlate to real-life time?

Best Answer

Yes, the game does follow the local time that your console or PC is set to. Not only that, it matches the sunset/sunrise times based on current time of year/month. Pretty cool. But sucks if you only get to play at night.