Moving north-northwest over favorable conditions, the disturbance intensified to a tropical depression, while the JTWC issued a TCFA on the newly developed system.

Despite the rugged terrains of the country, the JTWC upgraded the system further to a Category 3, shortly before weakening as it moved offshore on Taiwan Strait.

It continued to weaken, with the JTWC also downgrading the system to a tropical storm, before making landfall near Fuzhou on July 31 before it was last noted by the next day.

[2] On the same day, the JTWC issued their first warning on Tropical Depression 11W, with its center located approximately 650 nm east-southeast of Luzon's northeastern tip.

[1] The depression soon entered the Philippine Area of Responsibility (PAR) early on July 26, assigning the name Isang from the PAGASA.

[2] Due to the moderate wind shear impacting the newly formed system, the development was slow; however, the overall environment of Isang was favorable.

[9] Twenty-one people are killed and about 30 persons are missing in the town of Kuang Fu, in eastern Hualien County, Taiwan.