A person cools off at Banpo Hangang Park in Seoul, Wednesday. Yonhap

The state weather agency issued a heat wave warning for most parts of Seoul on Wednesday, marking the capital's second alert of its kind this summer.

The Korea Meteorological Administration (KMA) upgraded a heat wave advisory to a full warning for eastern and southwestern parts of Seoul at 11 a.m., as a nationwide heat wave has recently gripped the country.

The agency issued the capital's first heat wave warning this summer on July 11.

A heat wave warning is issued when the maximum apparent temperature is expected to remain above 35 C for two or more consecutive days.