The weather function can be found in the middle right of the Banjo footer. Its only purpose is to identify a dramatic change in weather from the start of the game. This will be rare, and most scouts will not use it at all during the season. Use your best judgment for a dramatic change in weather. Examples include:
Sunny to noticeable rain (and vice versa)
Snowing to sunshine (and vice versa)
Heavy wind picks up substantially midgame
REMINDERS
DO NOT use this if there is poor weather to start the game. Inclement weather at kickoff will already be accounted for
DO NOT use this if the game is delayed due to inclement weather (lightning in the area). That would be a Danger button situation
You can exit this screen by tapping Back or deselecting Weather in the Footer.