How accurate are Punxsutawney Phil's Groundhog Day forecasts?
The rodent has been predicting the start of spring since 1887. But how good is Phil at his prognostications?
Celebrity groundhog Punxsutawney Phil emerged from his "burrow" on Friday (Feb. 2, 2024) as a crowd in his home town in Pennsylvania waited with bated breath, wondering if the rodent would see his shadow.
He didn't.
According to legend, this means spring will come early this year. If the groundhog had seen his shadow, then there would supposedly be six more weeks of winter.
Is Punxsutawney Phil usually right?
Phil the groundhog has been forecasting the seasons on Groundhog Day at Gobbler's Knob in Punxsutawney 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 137 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 7:25 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.
According to the Groundhog Club's records, which span from 1886 to 2017, the various incarnations of Punxsutawney Phil have predicted 107 forecasts of more winter and 18 of early spring. 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.
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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 cast a 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.
Punxsutawney Phil vs. weather forecasters
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 (NWS). 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% accurate or higher, then we consider that to be a good estimate."
When will spring 2024 start?
In 2024, Phil's predictions might be accurate in some parts of the country but wrong in others.
Meteorological spring is on March 1, and the spring equinox happens on March 19 in the Northern Hemisphere. While parts of the northern U.S. West and Midwest might see an early end to winter this year, chilly weather may continue for some time in the south, according to AccuWeather's team of long-range forecasters. For the first time in more than 700 days, snow fell in January across many major cities across the northeast, including New York City and Washington, D.C. There is a possibility for more snowstorms in the east through the first half of March, but it's likely to drop off in the latter half of the month, AccuWeather reported.
"We may actually see a warmup in the second half of March across the eastern U.S.," Paul Pastelok, an AccuWeather senior meteorologist, said.
In the southeast, frequent rainfall is expected, which could limit temperatures, meaning states in this region may experience a slow crawl toward spring rather than a sprint.
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.