Punxsutawney Phil’s approximate predictive accuracy is commonly estimated at 39%.
That figure comes from comparisons between Phil’s Groundhog Day forecasts and subsequent seasonal weather conditions. It is far below the playful claims made by the Punxsutawney Groundhog Club, whose tradition presents Phil as extraordinarily reliable and even describes him as effectively perfect.
The exact percentage depends on how researchers define a correct prediction, which years they include, and what counts as “early spring” or “six more weeks of winter.” Published estimates have placed Phil’s empirical accuracy roughly between 35% and 41%, making 39% a useful rounded figure for trivia.
The tradition itself descends from European Candlemas folklore. German immigrants in Pennsylvania adapted stories about shadow-casting animals, replacing animals such as hedgehogs with the local groundhog. Modern studies generally find that groundhog forecasts perform around chance, so Phil’s celebrity is cultural rather than scientific.