Key Points

A total of 2,900 patients had visited emergency rooms for heat-related conditions as of Wednesday since mid-May, when authorities launched the heat-related illness surveillance system. Of those patients, 16 have died, according to the Korea Disease Control and Prevention Agency (KDCA), Yonhap News Agency reported.

As the heat wave persists, daily cases of heat-related illnesses have exceeded 100 for nine consecutive days since July 22. Deaths have also been reported for four days in a row.

Compared with the same period last year, the number of patients has increased about 2.6 times, while the number of deaths more than doubled, the KDCA said.

Among the patients reported this year, heat exhaustion, commonly known as sunstroke, accounted for 60.7 per cent, followed by heat stroke at 16.4 per cent, heat cramps at 13.4 per cent and heat syncope at 8.1 per cent.

By age group, those aged 65 and older accounted for 31.7 per cent of the total patients.

Most parts of the country have come under heat wave alerts.

The state weather agency said Seoul has seen the largest number of tropical nights for any July this year as of Wednesday, adding the heat waves gripping the country are expected to intensify in the coming days.

A tropical night occurs when nighttime temperatures stay above 25 C from 6:01 pm to 9 am the following day.

Meanwhile, Seoul has experienced 22 tropical nights so far this month, setting a record high for July since modern weather observations began 117 years ago, the state weather service said on Thursday.

The nighttime temperature in the capital fell only to 29.3 degrees Celsius between Wednesday and Thursday, increasing the number of tropical nights in July to 22 days, the most since record-keeping began in 1908, according to the Korea Meteorological Administration (KMA).

The previous record was 21 days, set in July 1994. A tropical night refers to a phenomenon when nighttime temperatures stay above 25 degrees Celsius from 6:01 p.m. to 9 a.m. the following day.

With one more night left this month, the record could extend to 23 days, the KMA said, noting Seoul was already hit by tropical nights during 70 per cent of this month.

The KMA said last night's minimum temperature of 29.3 degrees Celsius is set to become the highest daily low for July on record, if the temperature does not fall below the level Thursday night. The previous record was 29.2 degrees Celsius, set on July 23, 2018.

The agency said the maximum daily temperatures will range from 31 degrees Celsius to 37 degrees Celsius nationwide on Thursday. Seoul, Daejeon and Daegu will see temperatures rise up to 36 degrees Celsius.

- IANS