GREENVILLE, N.C. (WNCT) – It’s a tale as old as the hills: spot a woolly worm with a thin brown stripe in the fall and you’re in for a long cold winter. But, could these tiny caterpillars really be nature’s weathermen?
After several years of research in the 1950’s, Dr. C. H. Curran at the American Museum of Natural History in New York found that woolly worms tend to have wider brown bands during milder winters in New York. Organizers of the Woolly Worm Festival, held every October in Avery County, N.C., claim the insects are very good at predicting winter weather.
Corey Davis, an applied climatologist with the State Climate Office of North Carolina, explains:
“The Woolly Worm Festival said that it was 84% or 85% accurate. The research we have done in our office found that it’s more like a coin flip. More like a 50/50 chance of a woolly worm being right in a year on the winter.”
Even if they don’t hold the key to winter forecasts, these furry critters can tell us a lot about weather.
“So basically these woolly worms as they grow in the spring, they shed their skin,” says Davis. “And every time they shed their skin, or molt, they get a little bit browner. So it turns out if you have a little bit warmer conditions late in the previous winter or late in the previous spring, then that actually helps those woolly worms to grow a little faster.”
Even though Davis has pretty much debunked this piece of folklore, he still keeps an eye on the forecast every year.
“It’s something fun to watch every winter about this time of year, and see what these things suggest might happen,” says Davis.
And in case you’re wondering, this year’s woolly worm forecast calls for a wet start to winter with a milder finish.