Early on July 10, Halong passed just south of Guam as a tropical storm, producing high waves and gusty winds on the island.

Subsequently, the typhoon weakened greatly while curving to the northeast, although it still passed near Okinawa with strong winds that left widespread power outages.

Halong struck southeastern Japan, dropping heavy rainfall and producing strong winds that left $89.8 million (¥10.3 billion 2002 JPY) in damage.

[2] Late that day, the Japan Meteorological Agency (JMA) [nb 3] upgraded the depression to Tropical Storm Halong near the island of Chuuk in the Federated States of Micronesia.

After a brief turn more toward the west, the storm passed about 140 km (87 mi) south of the southern tip of Guam at 0200 UTC on July 10; at the time, the JTWC estimated 1‑minute sustained winds of 165 km/h (103 mph),[1] although the JMA had maintained Halong as a tropical storm until upgrading to a typhoon at 1800 UTC that day.

[3] An approaching trough increased shear over Halong, and a weak ridge to the north restricted outflow; this briefly prevented significant intensification after the convection decreased.

[5] Early on July 13, the JTWC upgraded Halong to a super typhoon after the storm developed a well-defined eye 63 km (39 mi) in diameter.

[1] At its peak intensity, Typhoon Halong had gale-force winds that extended 415 km (258 mi) northeast of the center.

However, the typhoon began rapidly weakening due to increasing wind shear, and the eye quickly deteriorated.

[1] The combination of cool, dry air,[2] and the persistent wind shear removed the convection from the center by early on July 15, weakening Halong to tropical storm status.

[1] Due to the storm, all flights were canceled in Guam and the Northern Marianas Islands, and officials advised residents in low-lying areas to evacuate.

[8] Portions of the island, including Guam Memorial Hospital, had their power restored after Chataan, only to lose electricity during Halong.

[1] In the Ryukyu Islands of Japan, including Okinawa, Halong left more than 48,800 houses without power due to the strong winds.