[rainfreak]

With a little more detail...

Install the latest HTC Home Customizer (HHC). I have attached it for your convenience. Then do the following:

1. Open HHC.
2. Choose the Weather tab at the bottom.
3. For Database Type, choose Custom.
4. Add the City, State, Zip Code, and Country in the correct fields below.
5. Click the Save City to Custom Database button.
6. Click the Save soft key.
7. Click the Yes button to Apply and Save.

When you check your weather, you should be good with your city's forecast.