Thousands of people came out in the near-freezing temperatures to watch Phil make his prediction on Thursday.
Phil saw his shadow, and many people in the crowd booed. The region has had a very mild winter this year.
The Groundhog Day celebration is rooted in a German superstition that says if a hibernating animal casts a shadow on Feb. 2, the Christian holiday of Candlemas, winter will last another six weeks. If no shadow is seen, legend says, spring will come early.
Phil has now seen his shadow 100 times and hasn't seen it just 16 times since 1886, according to the Punxsutawney Groundhog Club's Inner Circle, which runs the event.
The Associated Press contributed to this report.