The forecast is based on whether the groundhog, after being woken from hibernation on February 2, can see his shadow.
If he does, spring is another six weeks away.
If not, winter is over.
The tradition has its roots in an old wives' tale brought by German immigrant farmers.
Punxsutawney held its first Groundhog Day in the 1800s, according to the website.
The spectacle, which has become a tourist attraction and was the subject of a Hollywood comedy with Bill Murray in 1983, first took place on February 2, 1887.

This is Phil's official forecast as read February 2nd, 2009 at sunrise at Gobbler's Knob:
Hear Ye Hear Ye
On Gobbler's Knob this glorious Groundhog Day, February 2nd, 2009
Punxsutawney Phil, Seer of Seers, Prognosticator of all Prognosticators
Awoke to the call of President Bill Cooper
And greeted his handlers, Ben Hughes and John Griffiths
After casting a joyful eye towards thousands of his faithful followers,
Punxsutawney Phil proclaimed:
"And a bright sky above me
Showed my shadow beside me.
So 6 more weeks of winter it will be."
The tradition has its roots in an old wives' tale brought by German immigrant farmers.
Punxsutawney held its first Groundhog Day in the 1800s, according to the website.
The spectacle, which has become a tourist attraction and was the subject of a Hollywood comedy with Bill Murray in 1983, first took place on February 2, 1887.

This is Phil's official forecast as read February 2nd, 2009 at sunrise at Gobbler's Knob:
Hear Ye Hear Ye
On Gobbler's Knob this glorious Groundhog Day, February 2nd, 2009
Punxsutawney Phil, Seer of Seers, Prognosticator of all Prognosticators
Awoke to the call of President Bill Cooper
And greeted his handlers, Ben Hughes and John Griffiths
After casting a joyful eye towards thousands of his faithful followers,
Punxsutawney Phil proclaimed:
"And a bright sky above me
Showed my shadow beside me.
So 6 more weeks of winter it will be."