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I Am Getting Reports Of Light Brown Woolly Worms This Year... Can They Really Predict Winter Weather?

It is the time of the year that people start talk about the infamous woolly worms! as you know, a lot of people talk about the color of the woolly worm and some even use it as a predictor for winter weather. Ken Thornhill sent me this picture (twitter) of a light brown / white woolly worm he found this year.


Facebook 2 pic


Facebook pic 2


Interestingly enough, last year at this time I was also getting reports of the light brown wolly worms in our area. Here is the real question ... can the woolly worm predict winter?


Woolly Worm ... Superstition Or Accurate Predictor Of Winter?


Let's start by looking at what a wolly worm is. The woolly worm is actually the tiger moths in the larva stage. The technical name for the woolly worm is Pyrrharctia Isabella. In the late summer / fall these woolly worms start to appear more and more. In case you didn't know, folklore says that thin brown bands on the woolly worms means a harsh winter is coming, wider brown banded woolly worms mean a mild winter,  nearly black woolly worms means a severe winter is coming, and finally the very light brown or white woolly worms mean a snowy winter according to the folklore.


The question remains... can the woolly worm accurately predict winter? There actually was research done in the 1950s for 8 years by Dr. C.H. Curran. At the time, Dr. Curran was the curator of insects at the American Museum of Natural History in New York. Dr. Curran found that generaly the wider the brown segments on the woolly worm the more mild the winter would be. I think you can see where the folklore was born. Since then, there have been independent tests done and most say the woolly worms are about as accurate at predicting the winter as flipping a coin.


In reality, the woolly worm can tell something about the weather, but only the winter past. To understand, we need to look a little more into how woolly worms grow. As the woolly worm grows through spring, they molt which means they shed their skin. Every time they shed their skin, more brown bands can occur. Basically it appears the more brown bands a woolly worm has can be an indicator of the age of each woolly worm or when it started to grow in the prior spring. Entomologist Mike Peters from UMASS says specifically that the colored bands on a woolly worm are "telling you about the previous year('s)" winter, not the upcoming winter.


The bottom line is the woolly worm is folklore and most scientists agree there is no correlation between the brown banding of the woolly worm and the upcoming winter.




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Ann Thomas Jones Most definitely when we had the ice storm the wolly worms was black..(black means bad brown means mild) Maybe white means blizzard like conditions?? My exfather in law always says count the fogs in August thats your days that will snow last year it was 7 for my area this year 10 so far...

We have tons of dragon flies in Upton, ky for some reason. Does that mean anything for the weather? I have never seen so many here before. They are every where at dusk.

Melissa, I have never heard of folklore connected with that. For what its worth, we have seen tons of sweat bees this summer at my house?

My mom,her mom,and her mother swore by it .

lisa, there are a lot of people that do. I can tell you that I get tons of photos of every single color every year. If you forecast all types of weather, then you can't miss. :)

Personally I don't pay much attention to the wooly worms when it comes to making my annual winter forecasts. Last year I predicted that we were going to have a bitterly cold winter, in fact I predicted that once it got cold it would stay cold except for a very brief warm up now and then. I was so sure that it was going to be a bitterly cold winter that I added extra insulation to my home. So how was I so sure? Observation. I noticed the huge numbers of birds heading south in September. I noticed all the animals stocking up on food for the winter in huge numbers. If you really want to know kind of winter it is going to be forget your computers and simply observe what is going on around you and that will tell you all you need to know.

I was raised with the idea from my dad . That you could tell the type of winter that was coming from the color of the fur on a wooly worm ! If a wooly worm had a light brown coat of hair ? It would generally be the sign of a mild winter ! If the wooly worm's coat was real dark or black ? That was an indication that it was going to be a very extreme harsh or frigid winter ! If there were black bands on each end of the wooly worm and a wide band of brown in between the black bands ? Then that was a sign that there would be a cold start with a mild stretch and then a cold ending of the winter season !

It is a good indicator of the weather. Although there are many other things that have been used. Persimmon see, bee's and many others. Their not 100%, yet neither is our weather meteorologist. Just a tool farmers use to use.

Just interesting:
"folklore says that thin brown bands on the woolly worms means a harsh winter is coming, wider brown banded woolly worms mean a mild winter, nearly black woolly worms means a severe winter is coming, and finally the very light brown or white woolly worms mean a snowy winter according to the folklore."
3/4 of those would be described as "bad weather," and many of them combine to a similar meaning anyway. Harsh could mean severely cold and snowy. Severe would mean harshly cold and snowy. Snowy, well, means snowy.
Only one doesn't describe something like that, and no matter how a winter turns out overall, if it snows once 4 inches, you could say the woolly worms were right, it was snowy. If there was a week stretch of mild weather, people would say it was mild over winter and the worms were right.

I have wily worms every where at my house we took some pics this morning and would love to share

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