Punxsutawney, Pa., isn’t the only town that uses an animal to predict the weather.

Every year, the Western North Carolina town of Banner Elk gets its winter weather forecast from one tiny but athletic Woolly Worm.

Since 1978, thousands of people have flooded the small village in October to celebrate the coming winter at the town’s Woolly Worm Festival. Groups of Woolly Worms—actually the larvae of the Isabella tiger moth—race up a length of string, and the fastest winner of several heats is used to determine how severe the coming winter will be. The owner of the winning caterpillar receives a $1,000 prize.

Roy Krege, who has lived in Banner Elk for 42 years, has been involved in the festival since its inception. He is known as Mr. Woolly Worm because of his passion and involvement in the event.

Krege says the Woolly Worm typically has 13 brown and black body segments. Each segment correlates to a week of winter. The darker the segments are, the more snow the area will get, and the lighter the segments, the less severe the winter will be.

“We claim an 87 percent accuracy rate,” Krege says. “Though some people might say we aren’t quite that accurate.”

Krege says contestants can also win smaller cash prizes of $25 and $100 for winning their heats. More than 1,000 worms enter the contest every year.

But don’t try to pump your worm full of performance enhancing drugs to help claim the cash prize. You’ll get caught and publicly humiliated.

“We have a group of doctors and nurses that set up a complete hospital for Woolly Worms,” he says. “They act as veterinarians and test the worm’s urine. No one has been found guilty of cheating so far, but a few times there have been questions about what’s happened to the worm’s hair—it looked like it had been slicked down to go faster.”

Sue Freeman, executive director of the Avery County Chamber, which hosts the event, says this year’s event, which will be held on Oct. 17 and 18, should attract more than 23,000 people, almost triple Banner Elk’s population.

The festival also features crafts, food vendors and live entertainment. The races begin around 10 a.m. and each heat consists of 20 worms. Races continue all day until the grand finale around 4 p.m.

The festival is co-sponsored by the Kiwanis Club of Banner Elk and a portion of the proceeds go to support various children’s charities throughout the county.

“It’s a great fun family event that we’ve expanded even more this year,” Freeman says.