My Galaxy 4 watch just went through a software update R870XXU1IXK1 and after the update my watch no longer showed the temperature in the weather app as fahrenheit. I can go in to the app settings under the weather app and change it from Celsius back to fahrenheit, but it changes back to celsius after a few hours. I'm not exactly sure when it changes back, it may be when the Bluetooth connection is broken with the phone. 

I've tried a different weather app, but the default can't be changed and a different app is useless considering it will not be connected to the tiles or face.