My iPhone 5s default weather app (yahoo) is always off on it's forecast by 10 degree F when using the GPS location based weather. For example, I live in Tucson Arizona. If I open the weather app and look at the forecast for my GPS location which it says is Tucson, it says the high today is 81 degrees F. That is not correct, today's high is 91 degrees F. If I add Tucson as a city on my weather app it shows the correct forecast. This is consistent no matter where I travel. I have to add the city of where I physically am in order for the forcast to be correct. Very weird bug if you ask me. Anyone else experience this?