Fall foliage in Pennsylvania

Pennsylvania runs from the northern plateau to the southeast over about three weeks, and because the elevation range is modest, latitude accounts for most of it. Pine Creek Gorge at Leonard Harrison and Colton Point, Wellsboro, and the Poconos around Ricketts Glen and Promised Land lead in the second week of October; the Laurel Highlands and the ridge-and-valley country follow in the third week; Lancaster County and the Philadelphia suburbs finish at the end of the month. Maple, birch and cherry color the north; oaks and hickories carry the south.

Color somewhere in the state: October
Trees: maple, birch, cherry, oak and hickory
Region: Mid-Atlantic

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

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 Pennsylvania you would like covered? Write to fallcastapp@gmail.com.