While not a national holiday, it is a day of great interest and is widely followed by school children and adults alike. With origins dating back to pagan Western Europe, Groundhog Day has a rich and varied history. Its arrival in the United States is closely linked to the arrival of the Pennsylvania Dutch in the 18th century. In Europe, the badger was the animal to watch; in America it became the Groundhog, also known as the Woodchuck.
February 2 is one of the four annual cross quarters - in this case the midpoint between Winter Solstice and the Spring Equinox. Traditionally if February 2nd, Candalmas, was sunny it indicated that more cold and snowy weather was on the way and if it rained or snowed spring was just around the corner. Therefore if the Groundhog sees his shadow, then the day is sunny and there will be more winter weather.
Groundhogs, as many forest mammals, like bears, badgers, and hedgehogs hibernate or sleep during the winter - the feeling amount medieval Europeans, was these animals had an internal alarm clock, which told them when to awaken as Spring approached. In 21st centenary America, the most famous Groundhog - Punxsutawney Phil, actually will be awoken the morning of February 2nd by his handlers and dressed in his tux for the occasion and he will whisper his prediction in his handlers anxiously awaiting ears.
In truth, his forecasting ability is not really important - his keepers will have consulted the forecast and will have his prediction ready. The awakening of Punxsutawney Phil is ceremonial and makes for a great pre-dawn celebration.
With its complex origins and largely ceremonial nature now - Groundhog Day is still a great reminder that we are half way through winter and that spring is just around the corner.