subfrigid
/ˌsʌbˈfrɪdʒɪd/adjective
Designating regions adjacent to the north and south frigid zones, i.e. immediately to the south and north (respectively) of the Arctic and Antarctic Circles; of, relating to, or inhabiting such regions. Also more generally: very cold, close to freezing.
Origin
Early 19th century. From sub- + frigid.