In this day and age, there are plenty of ways to get the weather forecast. We can catch a weather update on the news or tune into a channel entirely dedicated to the weather. We can consult a weather app on our phones or look to social media for updates.

Despite all this, every year on Feb. 2, we turn to an unassuming rodent, the groundhog, for an indication of whether we can plan for an early spring or will need to hunker down for another six weeks of winter.

While perhaps the most famous of these furry, four-legged meteorologists is Pennsylvania’s Punxsutawney Phil, other parts of North America—including New York (“Staten Island Chuck”), Connecticut (“Chuckles”), Alabama (“Birmingham Bill”), and Canada (“Shubenacadie Sam”)—celebrate Groundhog Day as well.

The forecast depends on whether Phil (or Chuck, or Chuckles, or Bill, or Sam) sees his shadow when he emerges from his burrow. If he does, and runs back into his burrow, we’re in for six more weeks of winter. If he doesn’t see his shadow, we can look forward to an early spring.

Today, Punxsutawney Phil stepped outside at just after 7 a.m. and, seeing his shadow, predicted six more weeks of winter.

Pennsylvania native Susan Setta, associate professor of philosophy and religion, speculated that Groundhog Day could have its roots in two different ancient celebrations that fall around the same time of year.

The old Christian tradition of Candlemas Day falls on Feb. 2, she said, and commemorates the purification of Jesus at the Temple. For this celebration, clergy light and then pass around candles to pay homage to Jesus, who is seen as a symbol of light.

Setta also pointed to Imbolc, an ancient Celtic pagan purification celebration held on Feb. 1 that marks the beginning of spring.

“Part of the way the church got people into the fold was to put on these really interesting festivals,” Setta said, noting the particularly big celebrations for Christmas and Easter.

She added, however, that the Groundhog Day celebrations we are familiar with bear almost no resemblance to either Candlemas or Imbolc. As she put it, “This one seems to have evolved very differently.”

The History Channel posits that German Christians expanded on the idea of Candlemas Day by selecting an animal, the hedgehog, as a means of predicting weather. Once they came to America, German settlers in Pennsylvania continued the tradition, but swapped the hedgehog for a groundhog, which are much more common in the Keystone State.

Then, in 1887, a newspaper editor who belonged to the Punxsutawney Groundhog Club—a group of groundhog hunters—declared that Phil, the local groundhog, was America’s only true weather-forecasting groundhog, and the rest, as they say, is history.

Still, though: Why do we look to a groundhog each year with bated breath, hoping for good news? The answer is simple.

“It’s fun,” Setta said.