Have you noticed the leaves already turning color around Puget Sound? Here's the science behind it.

You may have already noticed the changing color of the leaves in Washington — and fall is still weeks away.

There are a couple reasons why tree leaves are looking stressed. For starters, think back to when these leaves first started to form this spring. It was still pretty wet. The ground was saturated, and we had plenty of rain around.

Over the past few months, we’ve seen a bit of rain, but nowhere near the amount earlier this year. So the trees started out this spring with an ample supply of water that’s now basically dried up — and that puts stress on the leaves.

Another factor is that right now we have about as much daylight as we did in mid-April. With the daylight starting to fade more quickly, the trees begin to react. They start to shut off the flow of chlorophyll to the leaves, which is what keeps them that green color. Without the chlorophyll, we begin to see the yellows, oranges, and reds.