noun
tropical night; sultry night
In Japanese meteorology, specifically a night when the minimum temperature stays at or above 25°C. Commonly used in summer weather forecasts and everyday talk about hot, sleepless nights.
今夜は熱帯夜になりそうだ。
It looks like it's going to be a tropical night tonight.
熱帯夜が続くと、寝苦しくて体力
When tropical nights continue, it's hard to sleep and it drains your energy.