It’s Groundhog Day... again.
Resisting the temptation to just repost that link, I will observe that Groundhog Day the movie - magic time loop - is less weird than Groundhog
Day the tradition - using whether an animal sees its shadow to predict the length of winter. (As Steve D notes, fiction has to make sense.) Which would you be more likely to put into one of your sessions?
Of course I could see it getting into a game with a high enough Weird Level that it actually works, and various interested parties fight over whether this happens or not.