Apple 12 weather shows that the local weather must be turned on.

Open the "weather" application in your mobile phone first. The mobile phone will default to the weather forecast of a city. After opening it, click the "I" button in the lower right corner. Enter the settings.

After opening the settings, you can manually add any city.

If you feel troublesome, you can turn on gps positioning, and the mobile phone will automatically add the weather of the city where the mobile phone is located. If you travel, the weather can also show the name of the area where you arrived.