Korea recorded its longest streak of tropical nights this year, as a prolonged heat wave continued to grip the country throughout August, the state weather agency said Sunday.

The number of tropical nights reached 20.2 days this year, outnumbering 16.8 days in 1994 and 16.7 days in 2018 since the Korea Meteorological Administration (KMA) began compiling the data in 1973, according to the KMA.

A tropical night refers to a phenomenon when the nighttime temperatures stay above 25 C from 6:01 p.m. to 9 a.m. the following day, Yonhap reported, citing the KMA.

The number of tropical nights in August reached 11.3 days, in the first double-digit record for August, it added.

The number of days with daytime highs exceeding 33 C also came in at 23.2 days, the third highest since 31 days in 2018 and 29.6 days in 1994.

The KMA said that the peak of this year's heat wave has passed, but high temperatures will likely continue into September, especially in the first 10 days of the month.