I don't believe I am the first person to have said it, but I often start off the hikes I lead by saying "The forest has a story to tell, if you are just willing to listen". The story that the forest tells is very adeptly written and has a mind boggling cast of characters and countless subplots. Today we are going to delve into one of those subplots, the weather.
I have been using nature to help me predict the weather ever since I was a boy bailing hay as a hired hand during the summer months. More often than not the only way I would get a day off was if it rained. Since I hated watching the news I needed another way to learn the likelihood of impending changes in the weather. My Grandma Emma always used to say "If you see a Cardinal it will rain within a day". I thought it sounded dubious, but i watched for cardinals regardless. The amazing thing is that she appeared to be right! Every time I saw a male cardinal it would usually rain within 24 hours.
Over the years as I have observed nature more acutely with the help of a barometer I have adapted my late Grandmothers folk weather prediction. Whenever you hear a male Northern cardinal sing there will be a change in the weather;usually rain. I know you are skeptical, everyone is when i tell them. All I ask is that you observe it for yourself and get back to me.
Now I don't simply rely on the Northern cardinal for weather predictions when I'm in the field, I also look to the trees. The two trees I rely most heavily on are the Silver maple (Acer saccharinum) and the genus Oak (Quercus spp.). As there is a change in the weather, or more specifically, a change in barometric pressure the leaves of the Silver maples and oaks will turn over showing their lighter colored undersides. The reason for this is that the petioles (the stem that attaches the leaf to the tree) is thinner on one side than on the other. This causes the petiole to stretch, or shrink at different rates with changes in barometric pressure which in turn "flips" the leaf to show it's underside.
It takes only a slight change in barometric pressure for the Silver maple to turn it leaves which I use as an early warning system. Used in conjunction with the singing of the cardinal I can give myself advance warning of impending shifts in the weather. Now if I look to up a little later and see that the oak leaves have turned over I K-N-O-W that I am in for a serious change and I should start to look for shelter.
Now I'd like to put this all in the context of a scenario:
I am out hiking on relatively calm, pleasantly warm summer day. As I move down the trail I here a male cardinal start to sing his "What cheer! What cheer! What cheer!" song so I look for a Silver maple and notice the silvery green undersides of the leaves, I also note the the prevailing breeze is from the south. An hour later I come upon an Bur oak (Quercus macrocarpa) on an upland and I can see that it's leaves are turned over too, and that the breeze has picked up and shifted to the north. I decide to shorten my hike and head for the car. As I am driving home the anvil shaped thunderheads are looming on the horizon bringing with them rain, wind, and lightning.
So to wrap it up. Does the singing of the male cardinal guarantee rain in 24 hours? No, but I'd say that it works close to 90% of the time for me (yes, that high). Does the turning over of Silver maple a,d oak leaves always mean rain? No, it does however mean a change in the weather (i.e. It's hot and humid today, it will be cool and dryer tomorrow. It's not raining now, it will be later. It's been raining for two days, it will stop soon, etc...)
Of course there are other predictors of weather like if there is dew on the grass in the morning it won't rain that day, and I hope to visit these with you more in the future. Until then get outside!