Yilan: Schools and offices in Yilan County will be closed on Tuesday due to forecasted heavy rain, the county government announced Monday.

According to Focus Taiwan, the latest forecast from the Central Weather Administration (CWA) predicts significant rainfall between 8 p.m. Monday and 8 p.m. Tuesday, with expected accumulations of 200-400 millimeters in low-lying areas of Yilan County and 300-490 mm in mountainous areas.

Meanwhile, Taipei Mayor Chiang Wan-an stated in a Facebook post that all but four schools in the city’s mountainous regions will operate as usual on Tuesday, based on CWA forecasts of 150-250 mm of rain in low-lying areas and 250-450 mm in the mountains.

As of 8:30 p.m. Monday, the CWA’s Anpu weather station in Taipei’s Beitou District had recorded 412 mm of rainfall, marking the highest nationwide. The 10 stations reporting the most accumulated rainfall were located in Taipei and New Taipei.

The CWA updated its extreme rainfall advisory at 5:15 p.m., indicating that Keelung’s north coast, Taipei, New Taipei, and Yilan County are likely to experience extremely heavy or torrential rain. Heavy to extremely heavy rain is also expected in Taoyuan and Hsinchu counties, with heavy rain possible in Miaoli, Nantou, and Hualien counties. These advisories will stay in effect through Tuesday night.

The ongoing heavy rain is attributed to the interaction between seasonal northeasterly winds and the periphery of Tropical Storm Fengshen, which is expected to continue through Tuesday. However, the rainfall is unlikely to cease immediately afterward as the northeasterly winds persist.

Under the Operation Regulations on the Suspension of Offices and Classes Because of Natural Disasters, work and classes can be suspended if the storm radius of a tropical storm or typhoon is expected to pass within four hours, with average winds reaching Beaufort scale 7 or gusts reaching scale 10. Suspension is also allowed if 24-hour rainfall is forecast to reach specific thresholds, with 350 mm applying to Tainan, Pingtung County, Hualien County, and Yilan County, and when recent or likely disasters occur. Ultimately, the final decision rests with the local government.