How accurate is Punxsutawney Phil? Let’s look at the last few years of Groundhog Day predictions (2024)

Groundhog Day is nearly upon us, and some of you might be asking, “why are we consulting a groundhog about the weather?”

Provided you already know the cultural origins of the holiday - and if you don’t, you can read all about it here - what you’re really asking is: how accurate could Punxsutawney Phil’s predictions possibly be?

It’s true that, by some metrics, Punxsutawney Phil’s predictions aren’t the most accurate out there. An often-quoted metric is that he’s right about 39 percent of the time.

The National Centers for Environmental Information at the National Oceanic and Atmospheric Association gave Phil an accuracy rating of 40 percent over the past 10 years in 2021.

“In 2021, Phil forecast a “long winter” when he saw his shadow and predicted an additional six weeks of wintry temperatures,” the website reads. “In fact, the contiguous United States saw below average temperatures in February and above average temperatures in March of last year. Phil was 50/50 on his forecast.”

The website goes on to admit that “Predicting the arrival of springtime for an entire country, especially one with such varied regional climates as the United States, isn’t easy!” So let’s get a bit more specific: how accurate is Phil when it comes to predicting the weather in his own region - the Northeast of the United States?

FiveThirtyEight.com did some of their own number-crunching, and broke down Phil’s predictions, as well as several of his rivals in Groundhog Day-style prognostication.

On their website, they looked at the stats from 1994 through 2021, and the results for Phil vary pretty wildly by region. On average, it looks like he was right about 39 percent of the time, including for the Northeast. But in some regions, like the South, his average is as high as 50 percent.

But then again, what do we mean by “early spring?” What are the hard numbers to say whether or not Phil’s yes or no is “correct”?

“In fairness to Phil and his supposedly sterling record, evaluating these predictions is tricky,” FiveThirtyEight.com said. “What constitutes an early spring? Should a month with an average temperature 2 degrees higher than the historical average count as one? What about 5 degrees? What if all the snow melts and it’s warm and sunny for a week in February, but then March comes in like a lion?”

The website goes on to admit that both they and NOAA have an “early spring bias” in their numbers - if even one month has an above-average temperature for the year, that counts as an early spring in their eyes.

“Though a half-degree above average is hardly a delightfully early eruption of spring by most standards, it qualifies by our metric,” their website said.

Keeping that in mind, it’s easy to see why some of Phil’s rivals had far better marks if they also were biased towards making more frequent “early spring” predictions.

However, if you make the definition of an early spring a bit more stringent - say, increasing it to a five-degree above-average temperature for February or March, then Phil gets a big boost.

“Meanwhile, applying that same threshold to Phil’s predictions (from 1994 to 2021) actually improves his accuracy to 50 percent in his home region and 68 percent in the Northwest, South and Southeast,” they said.

Jumping from 39 percent to 68 percent is pretty dramatic - and 68 percent accuracy is a fair bit better than a coin toss. Just don’t go using this info to make bets on Phil’s predictions, because that’s not legal in Pennsylvania.

READ MORE: Groundhog Day betting odds: What are the chances that Punxsutawney Phil will see his shadow?

For more detailed breakdowns of Phil’s accuracy over the past 20 years, check out the NOAA website here or the FiveThirtyEight study here.

And don’t miss out on these other Groundhog Day stories here:

• Gov. Shapiro to join Punxsutawney Phil for Groundhog Day celebrations
• How to watch the Groundhog Day reveal if you can’t be in Punxsutawney
• Groundhog Day events outside of Punxsutawney: Celebrate with these rodent weather forecasters
• Pennsylvania’s Punxsutawney Phil to be inducted into Meteorologist Hall of Fame