Why Do We Use a Groundhog to Forecast the Weather?

Jeff Swensen, Getty Images
Jeff Swensen, Getty Images | Jeff Swensen, Getty Images

It's only been in the past 60 or so years that humans have been able to rely on television meteorologists for weather predictions. Before Al Roker, the Babylonians looked at cloud formations; in 300 BCE, the Chinese had a calendar broken into 24 festivals, each with its own unique weather patterns.

Today we use satellites and other costly equipment to gauge our environment, examining changes in the atmosphere and running sophisticated computer models. And sometimes, we just stare at a groundhog.

Every February 2, a doughy rodent named Punxsutawney Phil briefly emerges from his winter hibernation to have a look around. If he sees his shadow, that means there will be six more weeks of winter. If he doesn't, we can assume that warm weather is looming.

The ritual has been carried out in Punxsutawney, Pennsylvania every year since 1887. Relying on Phil is actually far less reliable than flipping a coin—he's right an estimated 39 percent of the time—but clearly someone at one time believed a groundhog had predictive abilities. Who? And why?

To understand Phil's current status, it helps to know that superstition and weather have had a long association. Observers of the Christian holiday Candlemas, for example, received candles blessed by clergymen. If the skies were cloudy that day, warm weather was imminent; if the sun was out, winter would persist.

In Europe, the idea that winter's duration could be foretold was carried over to animal behavior. Hibernating animals like bears, marmots, and hedgehogs were observed to see when they'd emerge from their dens.

In Germany, the weather was anticipated by badgers. When Germans began settling in Pennsylvania, however, badgers weren't so readily available: The easiest hibernating animal to locate was the groundhog. In 1887, a newspaper editor began circulating the idea that one groundhog in particular, Punxsutawney Phil, was a meteorological wonder. Before long, the entire country became preoccupied with Phil’s prognosticating, and an annual tradition was born.

Phil isn't the only one in the business of long-range forecasting. The Old Farmer's Almanac, a yearly digest of upcoming weather patterns for large geographical areas, is prepared up to 18 months in advance: Its editors claim an 80 percent accuracy rate, though some meteorologists dispute the viability of assessing weather more than two weeks out.

In 2017, Phil "predicted" six more weeks of winter; it turned out to be the second-warmest February on record. In 2018, Phil again saw his shadow, but the month resulted in multiple new record high temperatures, including 80 degree days in typical winterscapes like Massachusetts and Washington, D.C., and several Midwestern and southern towns had record rainfall.

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