In America, a groundhog tells us when winter is over. In Switzerland, it’s the flaming head of a snowman that foretells the warmer weather.

Guild riders circle around the Böögg on the Sechseläuten meadow in Zurich. (Steffen Schmidt/AP)

Zurich’s Sechseläuten festival is an annual tradition that dates to medieval times. Back then, workers would work until sunset, but in the summer, they could leave at the toll of a 6 p.m. bell. Sechseläuten marks the first time in the season that the bell tolls, and it is celebrated with a parade on horseback and the burning of a snowman effigy — like Frosty the Snowman meets Wicker Man.

The snowman, called a Böögg, foretells the summer weather: The faster and hotter its fireworks-and-wadding body burns, the better the weather will be. This year’s Böögg burned in 12 minutes and seven seconds, beating the average of 13 minutes and 42 seconds, according to Swiss Info.

Is it a sign of global warming? Not really: The Böögg’s track record is worse than Punxsutawney Phil’s forecasting abilities. In 2007 the national weather service, MeteoSwiss, analyzed 50 years of Böögg data and found a correlation of “close to zero.”

A combination picture shows the Böögg, a snowman made of wadding and filled with firecrackers, burning atop a bonfire in the Sechseläuten square in Zurich. (CHRISTIAN HARTMANN/REUTERS)

Costumed children watch the Böögg. (CHRISTIAN HARTMANN/REUTERS)

As the bells of St. Peter's church chime 6 o'clock, the bonfire below the Böögg is set alight and mounted guildsmen gallop around the pyre to the tune of the Sechseläuten March. (CHRISTIAN HARTMANN/REUTERS)