Tomorrow's Weather / Possible New Typhoon to Affect Taiwan! 'Seven Consecutive Days of Heavy Rain Across Taiwan' Rain Intensifies from This Day — Full Week Ahead Forecast

Don’t forget to bring rain gear if heading out this weekend! According to the latest forecasts from the Central Weather Administration and WeatherRisk, enhanced southwest winds will bring the most significant rainfall to windward areas south of Chiayi. Greater Taipei and mountainous regions across Taiwan must remain vigilant against short-duration heavy afternoon downpours. Starting next Monday (17th), a low-pressure trough will continue affecting Taiwan through next Saturday, with large-scale winds shifting from easterly to southerly, causing rainfall zones to shift. Additionally, tropical disturbances forming between the South China Sea and east of the Philippines warrant close attention.

Weekend: Moisture-laden southwest winds bring heavy rain to areas south of Chiayi; northern regions guard against afternoon thunderstorms

Central Weather Administration forecaster Cheng-Chuan Chang noted that due to southwest winds, moisture levels remain high. Areas south of Chiayi will experience brief showers or thunderstorms, with a chance of localized heavy rain. Central Taiwan may also see isolated brief showers. While northern and eastern regions will be partly cloudy to sunny in the morning, isolated short-duration thunderstorms are likely in the afternoon. Northern areas, along with mountainous regions in central and eastern Taiwan, face a risk of localized heavy rain, with Greater Taipei especially vulnerable to short-duration downpours.

WeatherRisk added that upper-level westerly troughs moving eastward have pushed a broad low-pressure area northeastward, placing Taiwan on its southern flank and enhancing southwest winds. Southern regions on the windward side will see highs around 32–34°C, while relatively leeward northern and eastern areas may reach 33–35°C. The Taipei Basin and Huadong Valley could exceed 36°C, so while guarding against afternoon rain, sun protection and heat mitigation are also essential.

Future rainfall trends. (Image: Central Weather Administration)

Starting next Monday: Low-pressure trough continues; wind shift brings rainfall pattern reversal

As the low-pressure system responsible for southwest winds moves northeastward, Taiwan will remain under a low-pressure trough environment from next Monday (17th) through Saturday, resulting in a significant shift in wind direction.

Next Monday to Thursday (17th–20th) Winds shift to easterly to southeasterly. Rainfall patterns transition from 'rain in the south, dry in the north' to 'rain in the east, afternoon rain in the west.' Southern Taiwan, eastern regions (Hualien-Taitung, Hengchun Peninsula), and the northern Keelung coast will see isolated brief showers. Western Taiwan and mountainous areas in the east will be mostly cloudy, with isolated afternoon thunderstorms. Areas south of Hsinchu face a chance of localized heavy rain in the afternoon.

Next Friday to Saturday (21st–22nd) The low-pressure trough continues to affect the region, with winds shifting again to southerly. Southern and southeastern Taiwan will experience intermittent isolated showers or thunderstorms, with a chance of localized heavy rain. Elsewhere, skies will be mostly cloudy, with isolated heavy rain possible in central and northern Taiwan and other mountainous areas during the afternoon.

Will tropical disturbances develop? South China Sea to east of the Philippines under watch

Regarding potential typhoons or tropical depressions, forecaster Cheng-Chuan Chang stated that tropical disturbances could indeed develop within the low-pressure trough, with higher chances in the South China Sea. Current projections suggest any disturbance formed is more likely to move toward China, but formation location and track uncertainty remain high, requiring continuous monitoring.

WeatherRisk warns that during the latter half of next week, monsoon troughs in the South China Sea and east of the Philippines may each spawn a tropical disturbance. Particularly, the disturbance east of the Philippines has a higher chance of approaching Taiwan based on historical paths, and the latest developments of potential tropical depressions or typhoons must be closely monitored from late next week onward.