SPOKANE, Wash. — As fall is in full swing, many Inland Northwest residents are wondering when to expect the peak of fall foliage. 

Eastern Washington and North Idaho typically see the peak of fall leaves and plants between early and mid-October.

Some are already seeing a slow transformation with a few trees getting started early, already showing yellow, orange, and red colors on their leaves. 

An interactive fall foliage prediction map on a Smoky Mountains website says Idaho will see fall colors come sooner than eastern Washington.  

North Idaho, including Coeur d’Alene, can expect peak fall colors on trees around October 5. Eastern Washington will see peak fall colors just about a week later, around October 12.

Here is a look at October 5: 

fall colors 1
KREM

Here is October 12:

fall colors 2
KREM

Note the difference where by mid-October. While Spokane may be seeing peak fall colors, portions of North Idaho may be just passing their peak. 

For now, mid-to-late September is showing minimal to patchy fall colors, meaning widespread gold and orange will not come for about another month.

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KREM

You may be wondering: why do the colors of leaves change when enter the fall season?

The weather is a primary factor in this change. During the summer, leaves on trees are jam packed with chlorophyll, essential for growth and development through photosynthesis. However, as days get shorter in the fall and the sun angle decreases, leaves lose their chlorophyll. This means other compounds take lead and display a yellow or orange hue, followed by red and then brown colors. This also happens due to the cooling of temperatures and loss of sunlight.

Furthermore, some species of plants hold onto chlorophyll longer than others and take more or less time to start to see the shift.

Some spots of the country see fall appear quicker (or later) than normal depending on sunlight and temperatures toward the end of summer and start of fall.

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