Typhoon Zeke
Typhoon Zeke developed from a tropical disturbance in the Western Pacific monsoon trough southwest of Guam. Increased convection associated with the disturbance was first monitored by the Joint Typhoon Warning Center (JTWC) at 06:00 UTC on July 6, 1991. Following evidence that the disturbance had developed a low pressure center, the JTWC issued a Tropical Cyclone Formation Alert early on July 9. Two hours later, the Japan Meteorological Agency (JMA) upgraded the system into a tropical depression. After a steady increase in deep convection near the center of the system, the JTWC declared it a tropical depression at noon on July 9.
Tracking west-northwest at under the influence of a subtropical ridge to the north, the depression made landfall south-southwest of Manila. The depression tracked across the Luzon as it accelerated to the northwest in response to a surge in the southwesterly monsoonal flow over the South China Sea and emerged into the South China Sea on July 10, when it was upgraded into a tropical storm by the JTWC and JMA, with the former naming it "Zeke". Reports from ships in the South China Sea indicated a highly asymmetric wind profile, with the radius of winds extending over southeast of the center, but less than to the northwest, making its structure akin to a large monsoon depression. Despite the Navy Global Environmental Model and in turn the JTWC calling for recurvature, Zeke reverted to a largely westward track. On the morning of July 11, Zeke was upgraded into a severe tropical storm by the JMA. Twenty-four hours later, the JTWC declared the cyclone a typhoon. Shortly before Zeke struck Hainan, the JTWC estimated that Zeke attained its peak intensity of . Meanwhile, the JMA estimated that Zeke obtained its peak wind speed of and a minimum barometric pressure of . Zeke weakened slightly after crossing the island, with the JMA downgrading the system into a severe tropical storm on the morning of July 13. Later that day, Zeke moved onshore about northeast of Haiphong in Vietnam. Weakening accelerated as it moved inland, and by midday on July 14, the JTWC had ceased tracking the storm. The JMA followed suit early the next day. During its formative stages, the depression left two people reported as missing and injured three people across the Philippines. Zeke was responsible for heavy damage across Hainan, the most southern province in China. Power was knocked out in five counties in the province. According to press reports, 30 people were killed there and 77 others were injured. Close to 3,700 houses collapsed, and 58,103 others were damaged. At least of farmland was inundated, and 9.33 million rubber trees and of fishery ponds were destroyed. Eighty-three vessels sank. Additionally, the storm destroyed 28,000 head of livestock, of highways, 38 bridges, and of power lines. Monetary damage in the province was estimated at ¥5.1 billion (US$956 million). In the province of Guangxi, at least one person was killed and another was injured. There, over 180 houses were destroyed and 5,000 others were damaged. About of paddy field were damaged. Offshore Fangchenggang, two people died, seven were missing, and nineteen survived after a Vietnamese cargo vessel sank. In western Guangdong, where 1,170 houses collapsed and 11,700 others were damaged, four people went missing. More than of farmland was destroyed. Damage was estimated at about ¥19.4 million (US$3.63 million). Zeke was the first of two typhoons to hit China in a week, the second being Typhoon Amy. In Hong Kong, a No. 1 hurricane scale was declared at 00:50 UTC on July 12 when Zeke was about to the south. As winds across Hong Kong continued to increase and Zeke made its closest approach to the area, a No. 3 signal was issued. The lowest sea-level pressure of was recorded at the Hong Kong Royal Observatory just before noon on July 12. A peak of of rainfall was recorded in Tai Mo Shan, where winds of and gusts of were measured. All signals were dropped by the end of the day as the threat subsided.
Meteorological history
Tracking west-northwestward, the disturbance organized into a tropical depression on July 9. After tracking across the Philippines, where it left two people missing and injured three others, the depression intensified into a tropical storm on July 10. The storm steadily deepened as it moved across the South China Sea, and on July 12 it strengthened into a typhoon. While at its peak intensity of , Zeke moved onshore at Hainan, where it began to weaken. The system tracked across Vietnam on July 13, and dissipated within two days after moving inland.