Porter Peak is set in the Boundary Ranges of the Coast Mountains.

It is located 17 miles (27 km) north-northeast of Petersburg on land managed by Tongass National Forest.

[2] Although modest in elevation, relief is significant as the mountain rises up from tidewater of Thomas Bay in less than two miles (3.2 km).

[9] Weather systems coming off the Gulf of Alaska are forced upwards by the Coast Mountains (orographic lift), causing heavy precipitation in the form of rainfall and snowfall.

This climate supports a small unnamed glacier on the mountain's north slope.