Tropical Storm Prapiroon (2024)

Severe Tropical Storm Prapiroon (Thai: พระพิรุณ), known in the Philippines as Tropical Depression Butchoy, was a compact tropical cyclone that made landfall in Hainan and Vietnam in late July 2024. The fourth named storm of the annual typhoon season, Prapiroon was first identified as an area of persistent convection southeast of Manila on July 15. Several days later, the low-pressure system moved into the South China Sea. While tracking northwestward along the southern periphery of a mid-level subtropical ridge, the system intensified into a tropical storm and was named Prapiroon by the Japan Meteorological Agency (JMA) around 00:00 UTC on July 21. A few hours later, wind shear and dry air entrainment began to affect the storm. Despite these conditions, deep convection developed near the center during the next six hours, resulting in a compact structure as it approached Hainan. Prapiroon made landfall near Wanning, Hainan, with winds of 95 km/h (60 mph). After landfall, the storm maintained a well-defined eye while crossing central Hainan, leading the JMA to upgrade it to a severe tropical storm at 00:00 UTC on July 23. On July 22, the JMA estimated peak 10-minute sustained winds of 100 km/h (65 mph) and a minimum barometric pressure of 985 hPa (29.09 inHg). Later the same day, Prapiroon made a second landfall in Quảng Ninh, Vietnam, becoming the first tropical cyclone to strike the country in 640 days. The JMA indicated that the storm dissipated on July 25.

Prapiroon and its precursor, Typhoon Gaemi, enhanced the southwest monsoon over the Philippines, producing significant rainfall across parts of the archipelago. In China, twelve counties and cities on Hainan recorded rainfall totals exceeding 100 mm (3.9 in). The remnants of Prapiroon also contributed to heavy monsoonal rains in parts of Thailand and Cambodia. In total, the storm caused 23 deaths, nine people were reported missing, and damages were assessed at US$40.7 million.