Heat wave warnings and tropical night phenomena are expected to persist throughout this week, with sporadic rain continuing in the Greater Seoul area and some parts of Gangwon Province until the end of the week, according to the Korea Meteorological Administration on Monday.

On Tuesday, daytime temperatures are expected to reach as high as 36 degrees Celsius, with precipitation ranging between 5 to 30 millimeters for parts of Gyeonggi Province and Gangwon Province and 5 to 10 mm for much of Greater Seoul and northern parts of North Chungcheong Province.

The weather reports came as most parts of the country saw tropical nights on Monday, with temperatures remaining above 25 degrees Celsius, parts of Gangwon Province endured a "super tropical night," the KMA said.

According to the KMA, in Sokcho, Gangwon Province, the lowest overnight temperature was recorded at 30.6 C, marking it the hottest night on record since August 2008. The lowest temperature recorded in Gangneung, another city in Gangwon Province, reached 30.4 C.

A tropical night refers to a phenomenon where the lowest temperature remains above 25 C between 6:01 p.m. the night before and 9 a.m. the next day. If temperatures stay above 30 C throughout the night, it is dubbed a “super tropical night.”

The KMA added that other major cities were also hit with tropical nights, including Seoul, Incheon and Daegu where temperatures reached as high as 27.2 C, 26.6 C and 26.3 C, respectively.

“A tropical night phenomenon was observed in most parts of the country overnight as the warm, humid southerly winds were constantly brought in by the North Pacific anticyclone, failing to cool down the temperatures that rose during the day,” said the KMA through an official statement.

Though cloudy skies were predicted across the country with small amounts of intermittent showers, heat wave warnings were issued nationwide on Monday, continuing from those issued over the weekend.

According to the KMA, average daytime temperatures nationwide on Monday were expected to be above 30 C. However, due to humidity levels, temperatures felt as hot as 35 C in certain parts of the country.

On Monday, heat wave warnings were issued at the “alert” level for most parts of the country. Heat wave warnings at the “alert” level -- the third highest in its four-tier system -- are activated when the highest apparent temperature is forecast to exceed 35 C for two consecutive days or more.

Seoul expected daytime temperatures on Monday to reach as high as 30 C, while other cities like Jeonju and Daegu were to see temperatures reach as high as 34 C and 36 C, respectively. In Gangneung, daytime temperatures were expected to reach as high as 35 C.

Due to the number of days with scorching heat, a rapid increase in the number of patients with heat-related illnesses was observed from July 22 to Saturday. According to the Korea Disease Control and Prevention Agency on Monday, up to 289 patients were recorded over the six days. Since May 20, the agency has seen up to 925 cases of heat-related illnesses.