The weather card on Google Now used to be multiple stacks to show different cities. But Google has changed that and opted to place multiple cities in a single card. Of course, it initially shows you the weather in your city but if Google Now knows you will be traveling, it will show you the weather in those places you will be going to. We like how it provides a quick glance at all that information you will need. The update is supposedly rolling out so expect to see it on your Android device soon.
Source: Droid Life