Typhoon Champi: shifting forecasts put Korea's Jeju and Japan's Okinawa on alert

Typhoon Champi, designated the 30th tropical cyclone of the 2026 western Pacific season, has reached one of the highest intensity ratings of the year as it tracks toward the waters between Taiwan, Okinawa and the Korean peninsula. Forecasts from South Korean, Japanese and U.S. agencies have shifted over the past several days, and officials in both South Korea and Japan have issued precautionary warnings even though the storm's final path is not yet settled.

How strong is Champi, and why do the numbers differ

According to South Korea's Yonhap-affiliated newspaper Kyeonggi, Champi was located about 1,080 km south-southeast of Okinawa on October 21, with maximum sustained winds of 209 km/h, placing it at "Intensity 5," the top category on the Korea Meteorological Administration's (KMA) scale. Japanese weather service Weathernews, citing the Japan Meteorological Agency (JMA), reported a central pressure of 900 hPa at 3 a.m. on October 21, with sustained winds near the center of 60 meters per second (about 216 km/h) and gusts up to 85 m/s. U.S. outlet FoxWeather reported that the storm's one-minute sustained winds, as tracked by the U.S. Joint Typhoon Warning Center, reached 185 mph (about 298 km/h), a level the outlet said ties Super Typhoon Sinlaku as the strongest tropical cyclone recorded anywhere in the world so far in 2026.

The differing figures largely reflect the fact that agencies measure sustained wind over different time windows — the JMA and KMA typically report 10-minute averages, while the JTWC reports one-minute averages, which produce higher numbers for the same storm — as well as the fact that each reading was taken at a different time as Champi's strength fluctuated.

Forecast track: agencies disagree on where it turns

As of October 20, South Korea's IMBC reported that the KMA's main forecast had Champi moving northwest to strike northern Taiwan early on October 24, then making landfall on the Chinese coast between Fuzhou and Shanghai as a weakened Category 2 system. The U.S. JTWC, however, suggested the storm could turn north before reaching Taiwan and move toward "the area between Korea and Japan," while the JMA floated a sharper northward turn near Taiwan toward China's eastern coast. IMBC's report stressed that a typhoon's path can change dramatically depending on weather conditions.

By October 21, Kyeonggi reported an updated KMA track showing Champi moving northwest and then shifting northeast around October 25, bringing it to within roughly 320 km south of Seogwipo, on Jeju Island, by 3 a.m. on October 26. The KMA projected the storm would weaken steadily over that period, from about 140 km/h on October 24 to roughly 72 km/h by the time it nears Jeju, with a wind radius of about 280 km — large enough that Jeju and surrounding Korean waters could still feel strong winds and waves even without a direct hit.

Impact on South Korea

Newsis reported that South Korea's coast guard issued a maritime "caution" alert for Jeju's waters covering October 21-24, citing expected deterioration in sea conditions. The coast guard forecast maximum sustained winds of 14 meters per second and waves of about 3 meters around Jeju's southern waters, and activated its coastal safety accident risk-warning system. Officials advised residents and coastal visitors to avoid rocky shorelines and breakwaters and to stay out of hazardous areas, while patrol boats were deployed near fishing grounds and jetties and alerts were sent to vessel operators.

Impact on Japan and Okinawa

Weathernews reported that Champi was expected to approach waters south of Okinawa Prefecture on October 22-23 while still classified as "very strong," with the Miyako and Yaeyama island groups facing a 72% to 91% probability of entering the storm's violent-wind zone. Ocean swells of 6 meters or more were forecast around Okinawa by October 22, with gusts potentially exceeding 40 m/s in the Sakishima Islands by October 23. After passing Okinawa, the JMA-based forecast has Champi curving north through the East China Sea toward western Japan, though Weathernews noted that model uncertainty over the final track persists.

Background: an unusually active season

The Korea JoongAng Daily noted that Champi is the 30th named typhoon of the 2026 season, already surpassing the historical annual average of 25.1 storms. Weathernews reported that reaching a 30th typhoon this early in the year had not happened since 2013, a 13-year gap, underscoring how active the season has been. FoxWeather reported that Champi passed about 10 miles off Guam's southern tip over the preceding weekend before continuing to intensify toward the waters near Taiwan and Okinawa.