Woolly worms/wooly bears (Pyrrharctia isabella), larvae of Isabella tiger moths, are common throughout the fall. They are thought by some to be endowed with the ability of forecast upcoming winter weather conditions. There is no basis or data that supports this supposition, but folklore is always fun and it is arthropod-related, so here I go!
A few generalizations…
Black and brown banded – Bolder black bands forecast cold; wide brown bands forecast milder weather.
White woolly worms indicate heavier than average snows.
All white as well as all black worms in combination forecast a long, cold spell accompanied with deep snow.
Spiky protrusions forecast ice.
Woollier than normal forecasts cold.