subtropical high

(meteorology) One of the semipermanent highs of the subtropical high-pressure belt; these highs appear as centers of action on mean charts of surface pressure; they lie over oceans and are best developed in the summer season. Also known as oceanic anticyclone; oceanic high; subtropical anticyclone.

Areas of high pressure brought about when air which has risen in the tropics subsides in subtropical areas. The air is warmed adiabatically as it descends; therefore rainfall is unlikely.

Some authorities think that the subtropical anticyclones are the key to the world's surface winds, as they affect both the trade winds and the westerlies.