The origins of Tropical Storm Soulik can be traced back to September 14, when the Japan Meteorological Agency (JMA) reported that a low-pressure area had formed approximately 596 km (371 mi) east-northeast of Manila, Philippines.

[1][2] At 00:00 UTC on September 15, the JMA identified the system as a tropical depression, featuring a defined, partially exposed low-level circulation and persistent deep convection over the southwest quadrant.

[3][4] At 13:00 UTC on September 16, the United States Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert (TCFA), indicating that upper-level conditions were marginal, with low to moderate vertical wind shear and weak outflow aloft.

[12] On September 18, the JTWC canceled their TCFA due to an obscured low-level circulation with flaring convection, while the depression had drifted into an area of moderate vertical wind shear.

[13] Earlier, two disturbances in the South China Sea near 98W and 99W were expected to merge and strengthen at 98W, closer to Vietnam, and shortly after, the system was classified as tropical depression 16W, showing rapidly consolidating deep convection that has organized significantly over the past six hours.

[15] Early the following day, the depression intensified into a tropical storm named Soulik, according to the JMA, while heading towards the northern coast of Vietnam, though it was gradually weakening,[16] with peak 10-minute sustained winds estimated at 65 km/h (40 mph) and a minimum barometric pressure of 992 hPa (29.29 inHg).

[31] Prime Minister Phạm Minh Chính has instructed the People’s Committees in central provinces and cities to promptly implement their plans for responding to Tropical Storm Soulik.

[33][34] In Thailand, heavy rainfall caused by Soulik has led officials in Nakhon Phanom to quickly start water pumping operations into the Mekong River,[35] and Ao Phang Nga National Park will also be closed due to the weather conditions.