Citizens cool off near a fountain under Banpo Bridge in Seoul on Aug. 15, as tropical nights continued for the 26th day in a row in the capital. Yonhap

Seoul experienced its 26th consecutive tropical night on Friday, marking the longest streak of overnight temperatures remaining above 25 degrees Celsius in 118 years.

The temperature in Seoul did not drop below 26.8 degrees between 6:01 p.m. on Thursday and early Friday morning, extending its tropical night streak that began on July 21 to 26 consecutive days, according to the weather agency.

Tropical nights occur when temperatures remain at 25 degrees or higher from 6:01 p.m. until 9 a.m. the following day.

This is on par with the previous record of a 26-day streak set in 2018, which remains the longest since modern weather observations began in Seoul in 1907.

In 2018, the tropical night streak began on July 21 and ended on Aug. 15. However, this year's streak is expected to continue further, with overnight temperatures likely to remain above 26 degrees at least through Wednesday.

On Friday, the southeastern port city of Busan also recorded its 22nd consecutive tropical night, the longest streak since modern meteorological observations began in 1904 in the city.

Incheon experienced its 24th consecutive tropical night, the second longest streak for the city west of Seoul, following a 26 day-run in 2018.

On the southern island of Jeju, tropical nights continued for the 32nd day in a row. (Yonhap)