Groundhog Day is February 2nd each year, and has its roots in Astronomy. It is a crossquarter day, marking the midpoint between the winter solstice in December and the spring equinox in March. Although we celebrate the beginning of spring around March 21st, we begin to sense an end of winter, and anticipate the arrival of spring about now, the beginnings of February.
The tradition is simple: We watch the local groundhog and see if it will see its shadow or not. If the groundhog sees its shadow, then it will be scared, run back into its hole and we have to endure 6 more weeks of winter. If the groundhog does not see its shadow, then it will stay outside and we can expect an early spring.
The reasoning is also simple: If the weather on Groundhog Day is bright and sunny, then it is a nice day, we feel good, and don’t care too much that spring officially begins in about 6 weeks–the spring equinox. If the weather on Groundhog Day is grey and gloomy, then we laboriously plod through the day and hope for an early end to the doldrums of continued winter.
There are several weather-related origins to Groundhog Day that have included bears and badgers predicting the weather. Celtic tradition refers to the day as Imbolc, and uses a serpent as its weather prognosticator. Groundhog Day is also known in Christian tradition as Candlemas, and celebrates the purification of Mary and the presentation of the baby Jesus in the temple 40 days after his Christmas birth.