SEOUL, South Korea – South Korea is preparing for an unpredictable "Goblin Monsoon," set to begin across its central regions, including Seoul, from June 19. Forecasters warn of intense, localized downpours accompanied by strong gales, particularly from the afternoon of June 20, raising significant concerns about potential flood damage and increased discomfort due to rising humidity.

The Korea Meteorological Administration (KMA) notes this year's "Jangma" (monsoon season) is arriving earlier than average—approximately five days ahead for central areas, three for the south—due to the North Pacific High's rapid expansion.

Rain is forecast to start in Jeju on June 19 morning, spreading to Chungnam, Honam, and western Gyeongnam by afternoon, then extending to the metropolitan area, inland Gangwon, and Chungbuk by night. The KMA anticipates intermittent, heavy rainfall.

Expected precipitation from June 19-20 includes 20-60mm for Seoul, Incheon, Gyeonggi, inland/mountainous Gangwon, Daejeon, Sejong, and Chungcheong provinces (over 80mm possible in northern Gyeonggi/inland northern Gangwon). Other regions, like Gangwon's east coast, Gwangju, and Jeonnam, anticipate 5-20mm, with Gyeongnam, northern inland Gyeongbuk, and northeastern mountainous areas expecting 5-40mm.

The monsoon's intensity will surge from June 20 afternoon, especially in the metropolitan area and inland Gangwon, where violent downpours of 30-50mm per hour, with gales, thunder, and lightning, are forecast. Such rates severely impair driving visibility and quickly overwhelm urban drainage.

The KMA has issued urgent advisories: "Refrain from camping due to sudden rises in river water. Exercise extreme caution regarding low-lying area flooding, river overflowing, and rapid currents." The monsoon front's narrow, east-west oriented band suggests significant regional rainfall disparities, increasing localized flash flood risks. Rain may persist until dawn on June 21 for the metropolitan area and Gangwon, and until the afternoon for Chungcheong, southern regions, and Jeju, with some southern and Jeju areas seeing continued rain on June 22.

Beyond flood risks, increased humidity will elevate sensible temperatures. Unaffected areas may face heatwave advisories. Daytime highs on June 19 are forecasted between 25-34 degrees Celsius, with Seoul potentially reaching 32 degrees. June 20 and 21 highs are predicted at 24-31 and 24-30 degrees Celsius, respectively.

The ongoing heat and high humidity elevate the risk of heat-related illnesses, especially for vulnerable groups. The Korea Disease Control and Prevention Agency (KDCA) reported 185 cases this year (May 20-June 17), with no fatalities. To prevent illness, consistent hydration is crucial. Drink water regularly, even without feeling thirsty, as thirst signals dehydration. Caffeine and alcohol are ineffective for hydration due to their diuretic effects.

This "Goblin Monsoon," marked by unpredictable, heavy downpours, necessitates constant vigilance and adherence to official weather advisories.