 The lower formation is the late Devonian and early Mississippian Huntley Mountain Formation, which is made of relatively soft grayish-red shale and olive-gray sandstone.Outside the park the creek has cut down into the Devonian Catskill Formation, a reddish sandstone.The Allegheny Plateau has a continental climate, with occasional severe low temperatures in winter and average daily temperature ranges of 20 °F (11 °C) in winter and 26 °F (14 °C) in summer.