Heat wave warnings were issued for Seoul for the first time this summer season as sweltering temperatures prompted the city to raise its crisis alert from "caution" to "vigilance."

City officials said as of 10 a.m. Thursday, warnings were issued for eleven Seoul districts of Gangdong, Songpa, Gangnam, Seocho, Gangseo, Yangcheon, Guro, Yeongdeungpo, Dongjak, Gwanak and Geumcheon.

Under the elevated "vigilance” warning, the government began operating a comprehensive support situation room, with each district stocking up on emergency relief supplies.

Heat wave warnings are issued when the maximum heat index surpasses 35 degrees Celsius for two or more consecutive days.

Warnings are also in place for parts of Gyeonggi Province, the southeastern city of Daegu and Chilgok, North Gyeongsang Province, while heat wave advisories, issued when the maximum heat index surpasses 33 degrees, are in place for the rest of the country except for eastern coastal areas.

The Korea Meteorological Administration forecasts temperatures to begin dropping from Saturday.