PORTLAND, Ore. (KOIN) — It’s nice to have a lot of trees in the Pacific Northwest. It’s even sweeter when the leaves on those trees start turning into radiant hues of yellow, orange, and red — and we are just about to enter that timeframe!
We are nearing the time when our local scenery starts to turn a bit more colorful.
You can go ahead and watch the timeline in the video above. It is an estimation of when some of the Oregon counties and Washington’s Clark County will show off the best colors.
Fall leaves in the Portland area
For the Portland metro area, that sweet spot typically falls around the second to the third week of October. It’s not unheard of for some to already be seeing a leaf or two this early. You’ll really notice the change in the west hills and through the parks in about two weeks.
If you want to go for the prime time fall hike or you need to get some family photos, you may want to schedule for the weekend of October 15. Of course, depending on how windy the weather gets, this may change slightly. The estimation to be peaking here in the Portland area comes in four weeks. The farther you are north, the further along you will be with the fall foliage.
Best weather conditions
What are some of the weather conditions to help bring out some of the best colors? We do not want to be too hot or too cold. A mild sunny afternoon with a cool fall night that doesn’t drop to freezing will do the trick. You factor that in with a gentle wind, now we are in business.
When we have early wind and rain storms, they can strip the leaves prematurely before they can reach their peak color.
Additionally, anything too cold can halt the success of the transformation.
Summer heat can also stress trees, which from time to time, can happen near the end of summer. We are currently on track for some vibrant colors around here.
The colors
You may remember some of this from your biology class in school. The trick to the colorful transition is the breaking down of chlorophyll. Chlorophyll is the reason for the green pigments in our healthy trees.
How do we break it down? This is done naturally by limiting the amount of daylight. This is why there isn’t a significant difference year-to-year on when the fall colors start to change. The process is directed by the restricted daylight as we approach winter. As our day length shortens, the process is triggered.
Here are the three biology terms in regard to the different colors that tend to come out of the leaves, depending on the tree:
- Anthocyanin: The red or purple pigments that show up in the leaves.
- Xanthophyll: The yellow pigment that takes over.
- Beta-Carotene: The orange pigment that becomes more evident.
