Minneapolis, Groundhog's Day 2016. It's a snow sky, sunless and white: there's a big blizzard coming.
If you've ever wandered where the song-and-dance routine about the groundhog and his shadow comes from, it's a naturalized American version of some old European folk meteorology.
February 2 marks the mid-point of winter, and supposedly the hibernating animals come out of their hibernacula to reconnoiter. No groundhogs in Europe, so other animals do the job: bears, marmots, hedgehogs.
Traditional weather lore has lots of examples of days whose weather is said to portend what's coming. “If it's sunny on St. Whoozit's Day, the Sun will shine for the next 40 days.” Interestingly, Candlemas Day is the lone example when bad—cloudy—weather portends good weather coming. A cloudy Candlemas predicts only 6 more weeks of winter. (Which brings us, roughly, to the Equinox.) If it's sunny and clear instead, winter will last longer.