On July 21, both the JMA and the JTWC reported that Tropical Depression 08W had developed approximately 582 km (361 mi) to the south of Hong Kong.

[5] After drifting westward for a couple of days, the system strengthened into a tropical storm by JMA while nearing the island province of Hainan,[6] receiving the name Sonca.

[8] Early on July 25, the JTWC issued its final advisory as the system made landfall over in the Quảng Trị Province, Vietnam.

[9][10] During the storm, heavy floods were recorded in Vietnam, causing catastrophic property damage, submerging 229 villages.

[12] At least six people were killed when the storm made landfall on July 25, all in the provinces of Hà Tĩnh and Quảng Trị.

[13] In Nghe An Province, the total damage caused by the storm reached 127 billion dong (US$5.6 million).

[15] Tropical Storm Sonca affected four provinces across Cambodia, at least three people died, and 2686 houses were submerged.

[17] The National Committee for Disaster Management for Cambodia warned fishermen about the rough weather from the storm.