Hi Phil
Try out this. You always have an option to set customised wallpaper for both Lock Screen and Home Screen.
Choose your desired dynamic weather background for Lock Screen. Once you have done this, you have an option to customise the Home Screen in the next step. Choose photos and set your desired photo as Home Screen Wallpaper.
Alternately, Head to Settings>Wallpaper. You will find an option to customise your wallpapers of both lock screen and Home Screen from here. Choose your favourite picture for the home screen/ Lock Screen.
Hope this helps. Cheers