Seoul, Sep 10 (IANS): A heat wave warning was issued for all of Seoul on Tuesday, marking the first time the alert has been applied to the capital city in September since the heat advisory system was introduced in 2008, weather officials said.

The heat wave warning was issued starting at 4 p.m., an elevation from the heat wave advisory that had been in place since Sunday, according to the Korea Meteorological Administration (KMA).

A heat wave warning is issued when the feels-like temperature stays 35 degree Celsius or higher, while a heat wave advisory is issued when the perceived temperature is measured at 33 degree Celsius or higher, Yonhap news agency reported.

As of 4 p.m., the authorities had raised and expanded the heat wave alerts to special heat wave advisories for 167 out of 183 regions nationwide, meaning that almost the entire country is gripped by the scorching heat.

Many regions recorded their highest September temperatures. The Jeongseon county in the eastern Gangwon Province recorded 37.1 degree Celsius, with Seoul registering 33.9 degree Celsius. A dozen other cities and counties in the country's central region logged over 36 degree Celsius.

The scorching heat was expected to ease from Wednesday night, as the temperature is forecast to decline, the KMA said.

On Thursday, rainfall is expected for some central regions.