Trigger Instances in Skyrim
Solution 1:
Those events you are asking about are called Random Encounters and they're not just tied to the passage of time. There are specific locations where they are programmed to trigger.
Here is the relevant bit from the wiki:
Random encounters can occur at a large number of pre-fixed locations scattered around the game world. Different encounters can occur at the same location, if it is revisited after some time has passed.
So if you find a location that spawns a random encounter, just travel back there once in a while to see if another one spawns.