Mount Lebanon is a mountain summit in Liberty County, Montana, United States.
Mount Lebanon is part of the Sweet Grass Hills and ranks as the fifth-highest peak in the range, and fifth-highest in the county. It is situated north of Chester, Montana, and south of the CanadaâÂÂUnited States border. Precipitation runoff from the mountain drains into tributaries of the Milk River. Topographic relief is modest as the summit rises over above the surrounding plains in one mile. The landform's toponym has been officially adopted by the United States Board on Geographic Names.
Mount Lebanon is an exposed laccolith composed of diorite porphyry which was created by an igneous intrusion through older Cretaceous sedimentary rocks during the Eocene, about 50 million years ago. Over time, erosion of the sedimentary rock has exposed the solidified laccolith which is more resistant to weathering.
Based on the Köppen climate classification, Mount Lebanon is located in a semi-arid climate zone with long, cold, dry winters and hot summers with cool nights. Winter temperatures can drop below âÂÂ10 ðF with wind chill factors below âÂÂ30 ðF.