Can I retrieve the configuration data of the standard iPhone weather app?
The configuration information is stored in

/var/mobile/Library/Preferences/com.apple.weather.plist


This single property list contains all the preferences, including a 'Cities' array which holds info about each of the defined cities.

Whilst each city does have an 'UpdateTime' it doesn't contain when each city was selected and since all the cities are saved in the same file you can't use the date modified to tell when a city was selected.