Typhoon Zeke

Typhoon Zeke, known in the Philippines as Typhoon Etang, was the first of two typhoons to make landfall in China within a week during mid-July 1991. An area of disturbed weather developed east of the Philippines towards the end of the first week of July. 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 75 mph, 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.

Across Hainan, 30 people were killed and 77 others were injured. Nearly 3,700 homes were destroyed and over 58,000 others were damaged. Around 900,000 ha (2,200,000 acres) of farmland was flooded. Eighty-three ships sunk and thirty-eight bridges collapsed. Overall, 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 injured, while over 180 houses were destroyed and 5,000 others damaged. Offshore Fangchenggang, two people died and seven went missing after a ship sunk. Elsewhere, in the province of Guangdong, four people were reported missing and 1,170 homes were destroyed. More than 30,000 ha of farmland was destroyed, and overall damage was estimated at ¥19.4 million (US$3.63 million). Nationwide, 33 people were killed and 11 others were listed as missing.

Meteorological history
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 13 km/h under the influence of a subtropical ridge to the north, the depression made landfall 50 km 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 35 mph winds extending over 465 km southeast of the center, but less than 185 km 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 90 mph. Meanwhile, the JMA estimated that Zeke obtained its peak wind speed of 75 mph and a minimum barometric pressure of 970 mbar. 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 50 km 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.

Impact
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 900,000 ha of farmland was inundated, and 9.33 million rubber trees and 380 ha of fishery ponds were destroyed. Eighty-three vessels sank. Additionally, the storm destroyed 28,000 head of livestock, 718 km of highways, 38 bridges, and 1,282 km 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 20,000 ha 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 30,000 ha of farmland was destroyed. Damage was estimated at ¥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 640 km 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 1003 mbar was recorded at the Hong Kong Royal Observatory just before noon on July 12. A peak of 97 mm of rainfall was recorded in Tai Mo Shan, where winds of 79 km/h and gusts of 112 km/h were measured. All signals were dropped by the end of the day as the threat subsided.