As Taiwan experiences another wave of the northeast monsoon this week, three typhoons are forming in the Northwest Pacific, while another tropical depression is likely to strengthen into a record-breaking fourth. According to Taiwan's Central Weather Administration (CWA), typhoon Toraji and the nascent tropical storm Usagi could have notable impacts on Taiwan.
Toraji’s outer bands are expected to bring substantial moisture on Tuesday and Wednesday, especially in areas like Keelung’s northern coast, the Taipei mountains, and the northeastern region, where heavy to torrential rain is possible. Other regions may see an increase in cloud cover and rain, though precipitation will mainly affect eastern Taiwan, with only sporadic showers in central and southern areas.
Conditions will temporarily clear on Thursday, with most areas seeing partly cloudy to sunny weather. However, the tropical depression (TD29), currently near Guam, is projected to strengthen into typhoon Usagi and approach Taiwan on Friday. The impact on Taiwan will largely depend on whether it veers northward. Regardless, Usagi’s outer bands may bring significant rainfall to northern and eastern Taiwan, as well as the Hengchun Peninsula.
Fortunately, these four weather systems are spread far apart and are all moving generally west-northwest at around 20 km/h, making the likelihood of a "Fujiwhara effect", or merging of storms, very low.