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C. Alan Joyce

An Analysis of Punxsutawney Phil, the Great Weather-Predicting Chuck

February 2, 2010 —
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If all you know about Groundhog Day is what you learned from watching the Bill Murray movie, well… you’re actually quite well informed. The good people of Punxsutawney, Pennsylvania really do gather at Gobbler’s Knob each February 2 to find out whether a 20-pound groundhog named Punxsutawney Phil will see his shadow, thus foretelling six more weeks of winter—or not, foretelling an early spring.

In more than 120 years of predictions, there have only been 15 occasions on which Phil hasn’t seen his shadow. The National Climatic Data Center has estimated Phil’s accuracy rate at around 39%, but true Phil fans (or skeptics) can do their own analysis of Phil’s track record with Wolfram|Alpha.

Let’s take 1950, for example: according to Punxsutawney’s “Inner Circle,” Phil did not see his shadow that year. Ask about “punxsutawney, pennsylvannia weather feb. 2 1950,” and you discover that practically the entire day was overcast and foggy: not good conditions for a giant rodent to see his shadow. But an early spring? Check the results for “punxsutawney, pennsylvannia weather february 1950” and it’s hard to overlook the plunging temperatures and snowfall in the latter part of the month. Sorry, Phil.

How about 1970, another “no shadow” year? The results for Feb. 2 show cloudy skies and rain all day; the rest of the month brought just a tiny bit of snow, with temperatures surging several times into the 50s. Maybe Phil’s prognosticating skills got better with age?

If you’re curious, complete historical records of Phil’s predictions are available from the official website of the Punxsutawney Groundhog Club, so you can run your own analysis of Phil’s skills. (And fans of Marion, Ohio‘s Buckeye Chuck, or Lilburn, Georgia‘s General Beauregard Lee—or any of the world’s other great weather-predicting members of Marmota monax—can check local conditions for the chuck of their choice on Wolfram|Alpha.)


In Romania is the same tradition that on 2 feb. people are watching if a bear that is coming out of hibernation is seeing his shadow or not :)) .If the bear see his shadow, he is going back to hibernate and people say iti is going to be another one and a half month of winter !

Posted by ionut February 2, 2010 at 5:07 pm

39% accuracy is not too bad, is it…compared to some of the stock market analysts 😉

Posted by vJD February 3, 2010 at 6:26 am

There were so many people talking about Punxsutawney Phil on Twitter that it was one of the top trending topics for a while – check out the video at to see some of the more entertaining ones in a funny video. 🙂

Posted by TopTrendingTopics February 5, 2010 at 7:09 pm