Twin Typhoons Francisco and Co-May Bring Unstable Weather Across Taiwan

Taiwan, July 24, 2025 — Two tropical cyclones, Typhoons Francisco and Co-May, have developed in succession, resulting in unsettled weather conditions across Taiwan. According to Wu Derong, adjunct associate professor at National Central University’s Department of Atmospheric Sciences, the outer circulation of Typhoon Francisco is currently interacting with the southwest monsoon, bringing significant rainfall and gusty winds, particularly in northern and northeastern Taiwan. Afternoon showers or thunderstorms are also expected in the central and southern regions.

Based on the latest forecast issued by the Central Weather Administration at 2:00 AM today, Typhoon Francisco, a weak tropical system, is expected to pass through waters east of Taiwan before moving northward. The storm’s structure remains relatively loose. Meanwhile, Typhoon Co-May, also categorized as a light typhoon, is turning northeast after brushing the northwest of Luzon Island and is likely to weaken further. Both typhoons are moving under the influence of the southwest monsoon and are exhibiting signs of the Fujiwara effect, where two storms interact and rotate counter-clockwise around each other.

Wu also noted the development of a third tropical disturbance north of Guam. According to the European Centre for Medium-Range Weather Forecasts (ECMWF) model update from 8:00 PM on July 23, this system is intensifying but is expected to head northward without affecting Taiwan.

Temperature Forecast for Taiwan:

  • North: 24°C – 31°C

  • Central: 25°C – 33°C

  • South: 24°C – 35°C

  • East: 22°C – 34°C

From Friday through Sunday (July 25–27), the combined influence of Francisco and Co-May, along with monsoon winds, will continue to bring rain and strong gusts to central and northern areas. Localized thunderstorms remain possible in the southern region.

For early next week (July 28–30), Taiwan will remain under the influence of monsoon circulation. The atmosphere will stay unstable, with scattered showers across the island and strong convective activity expected in the afternoons. Residents should watch for severe localized weather, including lightning, strong winds, and heavy downpours. When the skies clear, the weather will remain hot and humid.

Authorities are urging the public to remain cautious, limit outdoor activities during periods of severe weather, and stay updated through official advisories as Taiwan continues to experience the impacts of these twin tropical systems.

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