A heavy rain advisory is in place for some parts of the Gangwon, North Gyeongsang and North Chungcheong provinces, with a special heavy rain advisory in effect for these areas, following torrential downpours in the morning in Seoul and central regions.

According to the Korea Meteorological Administration(KMA) on Thursday, 20 millimeters of rain per hour is falling in the counties of Jeongseon and Yeongwol in Gangwon Province and Danyang County in North Chungcheong Province.

Seoul and the capital region saw up to 30 millimeters per hour of precipitation in the wee hours, with some areas in the central region deluged with up to 70 millimeters per hour.

An emergency evacuation order was issued for residents near the Osan Stream in Gyeonggi Province, and for those in Dangjin, South Chungcheong Province.

The weather agency forecast that on Friday, southern regions will be battered with downpours with the stationary front causing the monsoon rain moving southward. 

The Jeolla provinces are set to see up to more than 120 millimeters of rain, the Gyeongsang provinces between 30 and 80 millimeters and the southern parts of South Chungcheong Province between 20 and 70 millimeters. 

The KMA projected that 30 millimeters of rain per hour will pound southern regions from early hours Friday to the afternoon with strong southwest winds bringing in a significant amount of water vapor. 

Usually, rains of 30 millimeters per hour hamper driving vision , even with windshield wipers at top speed. Rainfall of 50 millimeters per hour would trigger auto rain alert text messages and pedestrians would have to wade through rising water. At 70 millimeters per hour, water will pool at lowland areas and cause flooding in parking lots near rivers and streams.