Fall foliage in Idaho
Idaho’s color is concentrated along water at middle elevations rather than on the summits. Aspen and cottonwood around Sun Valley, McCall and Swan Valley turn in the first ten days of October, the Sawtooths and Stanley within the same week, and the western larch in the northern forests around Lake Pend Oreille goes gold at the same time. The Snake River plain and Boise finish in the third week of the month as the valley cottonwoods catch up.
- Color somewhere in the state
- October
- Trees
- aspen, cottonwood and western larch
- Region
- Rockies
Those are the months when color is present somewhere in Idaho, from its highest ground to its lowest. Any one location changes over a much shorter period than that.
Why the timing shifts from year to year
Shortening days start the process, so most places in Idaho change at close to their usual time each year. Within the state, elevation and latitude account for most of the difference: higher and more northern ground generally changes first, and lower, sheltered ground last. Weather has more effect on how strong the color is than on when it appears. Cool nights and sunny days favor the reds, a dry summer mutes them, and a hard freeze or a windstorm can strip a slope in a day. What determines the timing goes through this in detail.
Nearby states
Fall color does not follow state lines. Idaho borders:
- Montana fall foliage
- Nevada fall foliage
- Oregon fall foliage
- Utah fall foliage
- Washington fall foliage
- Wyoming fall foliage
Timing for a specific place
This page describes a whole state, which is about as precise as a season can be described in words. Conditions at one overlook on one weekend are a narrower question, and that is the one Fallcast answers: an expected period of color for a specific location, with a confidence attached, updated through the season as the trees change. It is coming to iPhone this fall.
Questions, or somewhere in Idaho you would like covered? Write to fallcastapp@gmail.com.