You probably need to SSH into the app directory and edit the file to reflect your city/zip code. On Windows, I use WinSCP. You could also use the Cydia app iFile to accomplish this without having to use a computer.
Open iFile and go to Library > Themes > Tycophone > jquery.simpleWeather.min.js > chose Text viewer > Scroll down to location:' ' > click Edit in the top left corner > type the name of your city and put it between the apostropes. It should look like this: 'Las Vegas' > then click save in the upper right corner > Respring.
Most of these weather apps will let you use the zip code instead of the city name, but the zip didn't work for me with this one so I used the city name instead. Glad to hear that adding in the state worked for you.