Garrison is a small village near Lough Melvin in County Fermanagh, Northern Ireland. The Roogagh River runs through the village. In the 2001 Census it had a population of 357 people. It is within the Fermanagh District Council area.According to the UK Met Office, the highest temperature ever recorded in Northern Ireland is 30.8 °C (87.4 °F) at Knockarevan, Garrison on 30 June 1976.