Fall foliage in Oregon

Oregon runs from the eastern mountains to the western valleys over about a month. Aspen and larch in the Wallowas and the Eagle Cap Wilderness turn in the first week of October, along with the high country around Crater Lake; the Cascades follow through the middle of the month; the Columbia Gorge, Hood River and the Willamette Valley finish at the very end of October and into November. Bigleaf maple, vine maple and cottonwood carry the west side in gold and orange against the firs.

Those are the months when color is present somewhere in Oregon, 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 Oregon 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. Oregon borders:

• California fall foliage
• Idaho fall foliage
• Nevada fall foliage
• Washington 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 Oregon you would like covered? Write to fallcastapp@gmail.com.