Animal Crossing: New Leaf for the 3Ds handles time in a different way as compared to most other games. The game progresses in real time even if you’re not playing, and the time in-game is set with respect to your system clock.
This means that is players play during the afternoon, it will be the afternoon in-game, and if it’s the summer in real life, then it’ll be summer in the game as well.
There are some disadvantages to this style of gameplay of course; if you’re the kind of person who only has time to play for about an hour or two in the morning/midnight, then you won’t be able to do much since all the shopkeepers and villagers in-game will be asleep.
The easiest way to circumvent this is to use the time travel feature in the game (although it’s not really in the spirit of the game).
To access time travel, you must talk to Isabelle about ‘other things’ when you meet her outside the village in the beginning of the game, and choose to set the time. Here you can decide everything about the time and set it to the minute.
The benefits of time travelling are quite clear, you can progress faster in the game by doing everything possible in a day quickly, then fast-forwarding to the next. You can make shop inventories cycle faster and repeat events that you missed in the past. You can even use it to play in different seasons and reach once-a-year events such as Halloween and Christmas.
There are some risks involved, however. Extensive time travelling can result in lots of weeds taking hold of the city, and flowers and trees dying. If you take a long trip through time some villagers may even move away without warning due to being neglected for so long.
You house will eventually get infested by cockroaches and possibly worst of all, you emerge from your house with a serious set of bed-hair. Also, since turnips are (for some reason) very sensitive to time paradoxes, any kind of time travel will instantly kill all turnips you have on you.