What does the stripes on a woolly bear worm mean, when it comes to predicting the weather?

On these last few warm sunny days you may notice Woolly Bear Caterpillars moving around looking for food and a safe spot to spend the winter. Some crawl in the crevices of tree bark, others under some dead leaves.

Does the length of the black and tan predict whether it will be a harsh winter or not?

Evan with an all orange woolly

No real study has ever been conducted. In 1948 Dr. Curran did a loose study where he recorded the stripe length of a small sampling of caterpillars and then the harshness of the following winter. His experiment was publicized in the paper and made the Woolly Bear Caterpillar one of the most recognized caterpillars in North America. Scientist today think, if anything, the stripes would tell what the last winter was, not the future. But no large study has ever been completed.

What would an all orange woolly bear caterpillar mean for winter?

Anna helps Evan with his woolly

According to the Old Farmer’s Almanac:
The wider that middle orange section is, the milder the coming winter. Conversely, a narrow brown band is said to predict a harsh winter. So an all orange woolly would mean a mild winter which is also what is being predicted for mid-Michigan by the Old Farmer’s Almanac:

“Winter will be slightly milder than normal, on average, with the coldest periods in lateNovember, mid-December, late January, and early and mid-February. Precipitation will be below normal, with near-normal snowfall. The snowiest periods will be in mid-December, mid- and late January, mid-February, and mid-March.”

Source: Old Farmer's Almanac:  http://www.almanac.com/