tropical air
From Glossary of Meteorology
A type of air mass with characteristics developed over low latitudes.
Maritime tropical air (mT), the principal type, is produced over the tropical and subtropical seas. It is very warm and humid and is frequently carried poleward on the western flanks of the subtropical highs. Continental tropical air (cT) is produced over subtropical arid regions and is hot and very dry.
See airmass classification, trade air;
compare polar air.