This was, without a doubt, one of the wettest summers we have had in many years. We have seen rainfall some 5-8 inches above the average for the summer. October is here and October is the driest month of the year. Based on the past 30 years, we typically see just over 3 inches of rain for the entire month. Temperatures begin to cool down nicely as well. Our average low temperature for the month is 53 degrees while our daytime high averages 73 degrees. That being said, the October Outlook from NOAA is suggesting temperatures may be warmer than normal for the month. It also looks like the frequent rain we saw over the summer will continue. Above average rainfall is also very likely.
October, as we all know, is when many of us head to the mountains for the fall color. The big question is, how will above normal rainfall affect the color? Here’s a little lesson on the chemistry happening in the trees. The fall color of a leaf is present from its formation, every leaf already contains pigments. When we see leaves in the height of summer, their green color comes from the production of lots of chlorophyll – that’s the green pigment that allows plants to make food from carbon dioxide and water which results from sunlight. As sunlight fades during the fall, chlorophyll production decreases and leaves lose their green. Without that green present, the other colors already in the leaves begin to emerge. Yellow pigment is produced by xanthophyll, orange-red color is caused by carotene and the reddish-purple color comes from the anthocyanin pigment.
What is needed for excellent fall color is lots of sunshine, providing the sugars in the leaves for pigment production. We also need some cool nights so the sugars don’t travel far from the leaf. It’s going to be a “wait and see what happens” month.
My other concern is the increased tropical activity we have seen this summer. During September, the Eastern Atlantic was the prime area for development. In October, the prime area is the Gulf of Mexico. It would be very bad for tropical squalls with strong winds. We would not have much to look at with few leaves left on the trees. I’d like to make some kind of prediction but the weather patterns seem to have their own mind these days.
Like everyone else, we will all be in a wait-and-see mode.