Punxsutawney Phil is widely regarded as the "official groundhog" used to predict the weather on Groundhog Day, February 2nd. If he pops his head out of his hole and sees his shadow, there's going to be 6 weeks more winter.
He lives in Punxsutawney, Pennsylvania, in a hill called Gobbler's Knob. Every year lots of people from the media gather there to see if he saw his shadow or not, often with live broadcasts. It's silly, but fun.
An influx of German immigrants to Pennsylvania brought along with them the tradition of hedgehog day, the idea being that if the hedgehog saw his shadow on Candlemas day, there would be six more weeks of winter. Since Pennsylvania didn't have many hedgehogs, they adapted it for the groundhog. For a more detailed look at the history of Groundhog Day, have a look at zgirll's writeup there.
In 1887, a group of people decided that there needed to be an "official groundhog" to do the predicting. So the group, calling themselves "The Punxsutawney Groundhog Club" began making trips every year on groundhog day to out to the wooded knoll, Gobbler's Knob, to check if the groundhog there, by the name of Punxsutawney Phil, saw his shadow.
It probably wouldn't have gone much further than that, if it wasn't for the fact that one of the members of the Punxsutawney Groundhog Club was the editor of the Punxsutawney town newspaper, the Punxsutawney Spirit. They published the results of Phil's prediction, and eventually Phil's fame spread.
Soon, he became not only the weather predicting rodent for Punxsutawney, but for the entire country.
Originally, the actual checking of if Phil saw his shadow was held in secret, with only the results being published. They started holding the ceremony in public 1966.
What happens is that Phil comes out of his burrow, looks around for his shadow, and then tells the Groundhog Club representative if he sees it or not. In "groundhogese," of course. Then it's translated and told to the media and the members of the public gathered there. Phil sees his shadow about 90% of the time.
The event has turned into quite the party. There's fireworks and music and other happenings going on from midnight until about dawn, which is when Phil is supposed to make his prediction.
The party has also gotten a lot bigger since the release of the 1993 hit movie Groundhog Day, which is hilarious and stars Bill Murray.
For Groundhog Day 2002, Phil shuffled out to find over 40,000 people awaiting his prediction...
He also found his shadow out there.
- Ever the drunkard, during prohibition, Phil demanded that he be given a drink, or else he'd impose an extra 60 weeks of winter.
- Phil declared that he was a "United States Chucknik", as opposed to a dirty commie Sputnik in 1958. Just acting a tad reactionary there, don't ya think?
- He made a visit to Washington, D.C. to meet with President Reagan in 1986. He took the trip with three members of the Punxsutawney Groundhog Club.
- He appeared on Oprah Winfrey's show in 1995. You go groundhog! I can't believe I just said that.