As a result of the Cold War and with the expansion of a North American continental air defence system, Lowther was selected as a site for a United States Air Force (USAF) radar station, one of the many that would make up the Pinetree Line of Ground-Control Intercept (GCI) radar sites.

Lowther Air Station, as it was referred to by the USAF, was declared operationally ready on 1 July 1958.

In early 1963 the 639th AC&WS was inactivated and preparations were made to transfer the station to the Royal Canadian Air Force.

In March 1963, Lowther AS was connected to the Semi Automatic Ground Environment (SAGE) system and the station became a long-range radar site.

Though there were still buildings and radar towers present, only three commissionaires remained to guard the once vibrant station.

This article incorporates public domain material from the Air Force Historical Research Agency