Fall is in the air. Temperatures are dropping, the sun is setting earlier, and everything pumpkin spice is back on the shelf. All we are missing is a little color in the leaves overhead. For all you fall lovers out there, those days are nigh.
The green in the leaves of summer comes from chlorophyll. Chlorophyll is the chemical in plants that turns sunlight and water into food through photosynthesis. As daylight hours shorten, the chlorophyll leaves the leaves and the green color fades, leaving behind the colors created by the other chemical compounds within the leaves themselves.
Temperatures do play a big role in leaf color, both in summer and in the months of cooling. Harsh conditions in the summer and the leaves don’t produce what it takes to get a brilliant show. A hard freeze in the fall and it all comes to an abrupt end. The perfect fall foliage is a finicky feat.
A good part of the Inland Northwest is facing some sort of drought following our hot, dry summer. Drought conditions put a strain on the leaves of trees and plants often resulting in dimmer colors come fall. While the I-90 corridor may be a bit more drab this year, parts of Northeast Washington and North Idaho should still put on a show.
Our temperatures now are trending much closer to those seasonal norms. Which many of you are calling cold. Longer-range forecast models suggest the somewhat “normal” trend continues in the weeks to come. That means we can expect a somewhat normal transition into fall colors.
So when will the change happen?
If you're going off the map above, that is based on peak color. That means, if you are heading out to see the leaves, it's better to go earlier than later so they don't drop before you get a chance to see them.
Obviously, it’ll happen in the mountains of North Idaho first. Those changes are already taking place, but the peak will likely occur in the first weeks of October. Lower elevations of North Idaho will take a little longer, most likely peaking sometime in the second week or so of October. Eastern Washington won’t be far behind, about a week later we can expect the leaves of Spokane and surrounding communities to do their thing. Central Washington always takes a little longer but it’ll get going by mid-October.
If there’s one thing we know, fall doesn’t last long around here. So when the leaves start changing, get out and enjoy the beautiful colors before the pre-snow brown sets in.
