The field that the weather widget uses is the Zip Code field for the "Day." Whenever you first add any record such as a Hotel or Venue to a day, the Day Location will be automatically populated. However you may override this if the weather service is not working properly.
To override the Zip used by the weather server, simply click on the City, State name in the upper-left part of the dashboard and edit fields will appear. In the zip-code field you can update the zip code to any value you like. In the case of some zip codes outside the US and UK, you can actually enter the city name in the zip code field. This field is used only for weather and location services so it will not display anywhere else.
Master Tour weather feature is powered by World Weather Online.