Hi
The following steps may help:
On your iPhone, in the Watch app, go to: My Watch (tab) > Weather > Default City > choose Current Location (or a specific location from those that have been added to the Weather app on your iPhone, if preferred).
On your iPhone, go to: Settings > Privacy > Location Services:
- Check that Location Services is enabled.
- If the setting is already turned on, try turning it off, pausing for a few moments and then re-enabling it.
- Check that Apple Watch Faces is set to While Using.
- Toggling the setting to Never and back again may help.
- Check that Weather is set to Always
- Toggling the setting may help.
At the bottom, tap on System Services > check that Setting Time Zone is enabled (you may also wish to enable all other system services, if they are not presently enabled).
Check that Bluetooth and Wi-Fi are both enabled on your iPhone:
- iPhone: Settings > Bluetooth - on.
- iPhone: Settings > Wi-Fi - on.
- For the best performance from your watch, keep both Bluetooth and Wi-Fi permanently enabled on your iPhone.
On your iPhone, go to: Settings > General > Background App Refresh:
- Check that Background App Refresh is enabled.
- It may also help to enable the setting for Weather.
On your iPhone, in the Watch app, go to: My Watch > Complications:
- If you are currently using a third-party weather app (such as Yahoo Weather) for your watch face complications, try removing it (via Edit, upper-right) and using Apple's built-in Weather app instead.
The following further steps may also help:
Restart both your iPhone and your watch, turning both devices off together, then restart your iPhone first;
Unpair and re-pair your Apple Watch: