Japan is enduring multiple weather systems, including Typhoons Mikla (Typhoon 7) and Hagibis (Typhoon 6), alongside a frontal rainband causing heavy rain and flooding, especially in western regions like Kyushu [1, 2, 3, 4, 5]. Typhoon Mikla, which formed on May 20 east of the Philippines, was near Okinawa on June 25 and moving northward, threatening southwestern islands and western Japan [1, 2]. Hagibis made landfall in early June, bringing heavy rains and flooding warnings; it was the first June typhoon to hit Japan in 14 years [3, 4, 5]. Miyazaki Prefecture issued a Level 4 Flood Danger Warning—the first under its new system—during Hagibis, with 309.5 mm of rain recorded in 24 hours on June 2 [4].
Despite Hagibis weakening to an extratropical cyclone by June 3, a new tropical depression formed in the South China Sea, continuing the risk of heavy rains in Japan [5]. The Japan Meteorological Agency warned of flooding risks through early June across Kyushu, Shikoku, Kinki, and Tokai from combined typhoon and frontal rain systems [1, 3, 4, 5]. In Owase City, Mie Prefecture, a 24-hour rainfall of 535.5 mm was recorded on June 3 [5].
In May, Japan experienced abnormal heat, with more than 90 observation sites reaching 30°C or higher and some areas hitting 35°C, raising heatstroke risks [6, 7]. Meanwhile, Taiwan recorded extreme temperatures above 38°C in early May, with 172 heat-related hospital visits by May 24 [8, 9, 10]. Cardiovascular risks rise sharply above 35°C, especially for elderly and chronic patients; doctors cautioned that sudden temperature changes increase heart stress and can trigger arrhythmias, ischemia, heart attacks, or strokes [8, 9, 10]. One cardiologist advised that air conditioning is the most effective way to cool down [10].
Taiwan’s Central Weather Bureau issued warnings for hot temperatures and heavy rains causing flooding, noting that Taipei's Neihu district received over 250 mm of rain on June 25 [2]. Nearby Singapore also faced hot weather and thunderstorms in May, with a record 114.6 mm of rain at Tampines on May 8 and rainfall in Paya Lebar rising 189% over average; there is now over an 80% chance of El Niño developing later this year, increasing risks of hotter and drier weather in the region [11, 12].
As of June 25, Typhoon Mikla remains near Okinawa and continues to threaten southwestern Japan, while northern Taiwan faces heavy rains and localized flooding [1, 2]. Authorities across the region remain alert for ongoing weather impacts.
