Temperatures will ease slightly from near 40 C, but much of western Korea will remain hot despite heavy rain hitting the east coast A child cools off in a splash fountain at Nammae Neighborhood Park in Gyeongsan, North Gyeongsang Province, Thursday, as a record-breaking heat wave continues across South Korea. (Newsis) South Korea’s near-40 degrees Celsius temperatures are expected to ease slightly over the weekend, but there will be no real break from the heat.Western regions will remain sweltering, while heavy rain could bring more than 150 millimeters to parts of the east coast through Sunday.FridaySeoul heads toward 39 CSeoul and Jeonju were forecast to reach 39 degrees Celsius on Friday, with Incheon and Gwangju hitting 38 C and Daejeon and Daegu 37 C.Temperatures had already climbed to around 30 C in several major cities by 8 a.m. after another tropical night.Friday, which marks Ipchu, traditionally considered the beginning of autumn, could become the hottest Ipchu ever recorded in Seoul. The previous record was 35.9 C in 2018.Highest-level heat warnings remain in effect for Seoul, parts of Gyeonggi Province, inland Gangwon Province and some southwestern areas.SaturdayShowers inland, rain in the eastTemperatures are expected to fall slightly Saturday as clouds block some of the intense sunlight, but daytime highs will still hover around 35 C in many areas.Rain will begin before dawn along the east coast of Gangwon Province and in nearby mountain areas before spreading to parts of the North Gyeongsang coast and Jeju.Scattered afternoon showers of 5 to 40 mm are also forecast across Seoul, Incheon, Gyeonggi Province and inland areas nationwide.The rain may briefly lower temperatures, but higher humidity afterward could make conditions feel just as uncomfortable.SundayHeavy rain along east coastRain will continue Sunday along the east coast, in parts of the southeast and on Jeju Island.The Gangwon coast and mountain areas are forecast to receive 30-100 mm from Saturday through Sunday, with more than 150 mm possible in some locations.Northern coastal areas of North Gyeongsang Province could receive 30-80 mm, while 20-60 mm is expected farther south.Flooding, landslides and swollen streams are possible in those areas.Western Korea, however, will remain hot. Easterly winds crossing the Taebaek Mountains are expected to become warmer and drier, keeping apparent temperatures near 35 C.What to know before heading outTropical nights are expected to continue through the weekend, meaning overnight temperatures staying above 25 C in many areas. People planning outdoor activities Saturday should prepare for sudden showers, while travelers heading to Gangwon Province or the east coast should check rainfall and road conditions.Strong winds, high waves and swells are also expected around Jeju and parts of the southern and eastern coasts. Beachgoers should avoid rocks, breakwaters and exposed coastal roads.