How accurate are Punxsutawney Phil's Groundhog Day forecasts?

A man in a suit and top hat holds a groundhog in front of a large crowd.
Punxsutawney Phil saw his shadow in Pennsylvania on Feb. 2, 2023, meaning six more weeks of winter, according to legend. (Image credit: Fatih Aktas/Anadolu Agency via Getty Images)

Celebrity groundhog Punxsutawney Phil emerged from his "burrow" on Thursday (Feb. 2, 2023) as a crowd in Punxsutawney, Pennsylvania waited with bated breath, wondering  if the rodent would see his shadow.

He did.

According to legend, there will be six more weeks of winter. If the groundhog hadn't seen his shadow, then spring would supposedly come early. 

Phil the groundhog has been forecasting the seasons on Groundhog Day at Gobbler's Knob since 1887, but just how good is he at his job?

Not very, it turns out.

Punxsutawney Phil's process for predicting spring hasn't changed much in the past 136 years. The Punxsutawney Groundhog Club takes care of Phil year-round, and on each Feb. 2, members of the club's Inner Circle rouse Phil at sunrise (this year he emerged at 7:22 a.m. EST) to see if he casts a shadow. Contrary to popular belief, Phil doesn't actually have to see his shadow; he just has to cast one to make his wintry prophecy.

Is Punxsutawney Phil usually right?

According to the Groundhog Club's records, the various incarnations of Punxsutawney Phil have predicted 108 forecasts of more winter and 20 early springs. There are nine years without any records, and even the Punxsutawney Area Chamber of Commerce, which keeps track of these things, doesn't know what happened to Phil during those years. Data from the Stormfax Almanac's data shows that Phil's six-week prognostications have been correct about 39% of the time. And a 2012 to 2021 study revealed that Phil was right only 40% of the time, according to the National Oceanic and Atmospheric Administration's National Centers for Environmental Information.

Phil does a shade poorer when you check his performance against actual weather outcomes since 1969, when the accuracy of weather records is less in question, said Tim Roche, a meteorologist at Weather Underground. From 1969 on, Phil's overall accuracy rate is about 36%.

The groundhog's powers of prognostication are slightly better when he doesn't see his shadow, though. "When Phil predicted a short winter, he was much more likely to be right," Roche previously told Live Science. "Out of the 15 times that he didn't see his shadow and predicted an early spring, he got it right seven times. That's a 47% accuracy rate," he said at the time. 

When will spring 2023 start?

In 2023, wintry weather may last even longer than Phil's predictions.  This year, meteorological spring is on March 1 and the spring equinox happens on March 20 in the Northern Hemisphere. Despite these upcoming dates, chilly weather may continue for some time. "The AccuWeather long-range team is concerned about a surge of cold and wintry weather right near the official start of spring. Before then, it may feel like spring at times, particularly across the Southeast and mid-Atlantic," Paul Pastelok, an AccuWeather senior meteorologist said

Even after spring starts, there will likely be waves of cold air and also opportunities for snowstorms and severe weather outbreaks, according to AccuWeather. But there will also be hints of summer weather interspersed in this mix.

So how does Phil stack up against human forecasters? "If Punxsutawney Phil is right 39% of the time, that's much, much worse than a climatological prediction," Roche said. "Even if you flip a coin, you'll still be right close to half of the time. That's a 50 percent accuracy rate. So you'll be better off flipping a coin than going by the groundhog's predictions."

Ouch. To rule out the possibility that Roche just has a thing against groundhogs, we checked Phil's performance with David Unger, a meteorologist at the National Weather Service. It looks like Phil probably won't be getting a job at the NWS any time soon, either.

"It's extremely difficult to give an estimate of how accurate climate predictions are," Unger told Live Science in 2011. "But compared to the terms with which Groundhog Day predictions are made, which are if the weather will be mild or not mild, then if our forecasts are about 60 percent accurate or higher, then we consider that to be a good estimate."

So there you go. Punxsutawney Phil's forecast raises awareness about the change of seasons. But he doesn't always get it right. Then again, what do you expect? Phil is a groundhog, after all.

Live Science Staff
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  • renelle67
    Of course he will see his shadow when they do it in the early morning with lights set up all around to view it.
    Reply