South Korea's first tropical night of 2024 hit Gangneung, Gangwon Province, on Monday night, a week earlier than last year, according to the Korea Meteorological Administration on Tuesday.

Tropical nights are defined as ones in which the temperature remains above 25 degrees Celsius from 6 p.m. to 9 a.m. the next day, according to the KMA. As of 6:50 a.m. Tuesday, the KMA announced that temperatures remained above 25 C in Gangneung and would remain the same or higher until 9 a.m.

It is the country’s first tropical night of the year, occurring seven days earlier than last year. In 2023, South Korea’s first tropical night was observed on June 16 in Yangyang, Gangwon Province. Gangneung saw its first tropical night of 2023 on June 28.

Monday night was the ninth earliest tropical night since 1912. The earliest tropical night ever observed was just five years ago, on May 24, 2019.

With warm air coming in from the west and strong sunlight due to high pressure from Mongolia, the KMA expects to see average daytime temperatures nationwide exceed 30 C throughout the week. Some cities located in the North and South Gyeongsang provinces can also expect to see daytime temperatures rise above 33 C this week.

As of 10 a.m. Tuesday morning, heat wave warnings -- issued when the highest apparent temperature is expected to reach 35 C or higher -- were issued in Yongin, Gyeonggi Province, as well as Damyang and Gokseong in South Jeolla Province.

Heat wave warnings that were issued Monday in Daegu, Ulsan and nearby cities in North and South Gyeongsang provinces were also maintained.

Meanwhile, daytime temperatures in cities like Gyeongju and Gyeongsan, South Gyeongsang Province, were expected to reach up to 35 C on Tuesday, while cities like Daegu expected to see temperatures hit 34 C. Daejeon and Gwangju could expect to see daytime highs of 32 C.

While it will likely get slightly cooler over the weekend due to clouds and rain that could fall on Saturday in some parts of Korea, the heat will not dissipate completely. Morning temperatures this weekend nationwide are expected to range between 19 C and 21 C, while daytime temperatures are expected to range between 26 C and 31 C, which is slightly higher compared to previous years.