Mild winter ahead? This little forecaster says 'Yes'

Weather folklore is always fun:

'Red sky at night, sailors delight.  Red sky in the morning, sailors take warning'
'Thunder in the fall foretells a cold winter'
'When leaves fall early, autumn and winter will be mild.  When leaves fall late, winter will be severe'
'When windows won't open, and the salt clogs the shaker, the weather will favor the umbrella maker'
'When a halo rings the moon or sun, rain's approaching on the run'

Photo: Diana Reuber
Freeport, IL

Some may dismiss those sayings as just that, weather sayings.  But a lot of the weather folklore comes from observation from the past.  So, there is a little truth to some of those old legends. 

One that you may be very familiar with is determining what the upcoming winter will be like by the looking at a woolly bear caterpillar.

According to the old legend, the wider the middle reddish/brown section is on the caterpillar, the milder the upcoming winter will be.  Conversely, the more narrow the reddish/brown section is on the caterpillar the more harsh winter will be.  But the big question is, is it true??

To fully understand just where this old saying came from, we have to look back at the history of how the woolly bear caterpillar became famous.

According to the Farmer's Almanac, in the fall of 1948, Dr. C. H. Curran, curator of insects at the American Museum of Natural History in New York City, took his wife to the city of Bear Mountain State Park to look at woolly bear caterpillars.  While there, Dr. Curran collected as many caterpillars as he could during the day to determine the average number of reddish/brown segments.  Using that information, he tried to forecast the upcoming winter with a reporter at The New York Herald Tribune.  It was through this experiment that the woolly bear caterpillar became famous.

So, did his experiment of eight years prove anything?  According to the Farmer's Almanac, between the years of 1948 and 1956 Dr. Curran's average brown-segment counts ranged from 5.3 to 5.6 out of the 13 segment total (total number of segments of the caterpillar).  This meant that the brown band took up more than a third of the woolly bear's body.  As those numbers suggested, the corresponding winters were milder than average.  Now, it's important to understand that Dr. Curran had no real scientific data to support this.  He knew his data samples were small and doing the experiment was more of an excuse for having fun.

Most in the scientific community think of this folklore as just that, folkore.  You'd have to look at many, many caterpillars across the country to try and figure out if there is any evidence that would support a relationship between the reddish/brown band width and winters.

But wait...Mike Peters, an entomologist at the University of Massachusetts, doesn't completely disagree that there is a link between the severity of winter and the width of the brown band.  He says, "There is evidence that the number of brown hairs has to do with the age of the caterpillar - how late it got going in spring.  The only thing is...it's telling you about the previous year's winter." 

So, while there might not be much truth to this old legend it's always fun to see how many of the woolly bear caterpillars you can find.  And while I haven't seen many yet, I'm going with what this little guy (or girl) is telling me...a mild winter!