プログレッシブ和英中辞典(第4版)の解説
こうきあつ【高気圧】
high atmospheric pressure; an area of high pressure; a high pressure zone
日本列島は高気圧に覆われている
The Japanese Islands are 「covered by [enveloped in] a high pressure system [area].／There is a high-pressure area over Japan.／A high-pressure area covers Japan.