Use Time Travel on your Apple Watch
Time Travel is a feature of watchOS 2 and later which lets you see what's ahead in your day. When you rotate the Digital Crown while your watch face is displayed, compatible complications will show you their status at the time you select rather than the current time. As an example, if you use the Weather complication, it will show the current temperature. If you use Time Travel and scroll to one hour in the future, the complication will show you what the forecast is at that time. Note that not all complications are compatible with Time Travel. The complication icon will be faded if it does not support Time Travel. For example, with the Activity complication, you can scroll backward to see how much progress you had made earlier in the day, but the icon will dim if you scroll forward as it cannot predict your progress later in the day.
Time Travel in action
With Time Travel, you can go backward up to the beginning of the previous day, or forward up to the end of the following day.
In watchOS 2.0 - 2.2.2, Time Travel is always enabled. In watchOS 3.0 and later, you will need to turn it on. To do so, grab your iPhone, and go to Watch > Notifications > Clock > Time Travel, and turn it on.
Not sure what version of watchOS you have? You can find out by going to Settings > General > About > Version. If you'd prefer to check on your iPhone instead of directly on the watch, you can go to Watch > My Watch > General > About > Version.