- Punxsutawney Phil has "predicted" an early spring in 2016
- Legend has it that groundhogs come out of hibernation on February 2 to test the weather
- Their foray into the cold is less about forecasting and more about mating, say experts
- Groundhogs are a pest to some gardeners and farmers, who take extreme measures to be rid of them
(CNN)For more than a century, groundhogs have been midwinter luminaries, scampering into the spotlight on February 2 to divine whether the second half of the season will be cold or mild.