1998 Pacific typhoon season

A La Niña swing after 1997

The Joint Typhoon Warning Center described 1998 as a pendulum swing from 1997. Its first warning, on Tropical Depression 01W east of Luzon, came on 7 July, the latest start to a season in its records since 1959, and Tropical Storm Nichole became the latest first named storm in that record. The center linked the delay to the La Niña that persisted through the year. It counted 27 tropical cyclones, four below its long-term average and the fewest in ten years, split evenly among 9 depressions, 9 tropical storms and 9 typhoons.

Formation shifted north and west. The JTWC counted 10 cyclones forming in the South China Sea, double its 15-year average for that region, 10 in the Philippine Sea and only 4 east of Guam, where formation fell 70 percent below average. 1998 was the least active season on record until 2010, and PAGASA recorded only eleven storms in the Philippine area of responsibility, its quietest year.

The site's archive counts 17 tropical storms, 10 typhoons, 5 major typhoons and 1 Category 5, with an accumulated cyclone energy of 152.1 from US-agency one-minute winds during the tropical stage. The JTWC's 18 storms of tropical strength include Tropical Storm 03W, upgraded after the season, and Tropical Storm Alex, which formed inside Zeb's circulation; the archive carries no wind values for either. The site's totals instead include the Bay of Bengal cyclone that grew from Tropical Storm Chip's remnants and peaked at 75 kt. Other season lists give 16 tropical storms and 8 typhoons under Japan Meteorological Agency ten-minute winds.

Otto, Rex and the summer storms

Typhoon Otto became the first typhoon on 3 August over water warmer than 30°C east of Luzon. It peaked at 100 kt just before striking southeastern Taiwan on 4 August, weakened over the mountains, then regained typhoon strength in the Taiwan Strait and came ashore near Fuzhou, where its rain added to flooding in Fujian. Flooding killed five people in Taiwan. Tropical Storm Penny crossed northern Luzon and came ashore near Zhanjiang on 11 August.

Typhoon Rex posed the year's hardest forecast. Three separate cells in the tropical upper-tropospheric trough pushed it off its expected northeast track, and it peaked at 115 kt on 28 August south of Japan. Rex never made landfall, but its approach to Honshu brought flooding and 575 mudslides. The JTWC cited media reports of 13 deaths and 8,000 homes destroyed; the combined rain of Rex and a stationary front killed 25 people in Japan, with daily totals over 600 mm at Nasu.

Typhoon Stella came ashore near Numazu on 15 September at minimal typhoon strength, and the JTWC cited press reports of 23-foot waves, 14 inches of rain in 24 hours and four deaths. Typhoon Todd formed in a reverse-oriented monsoon trough and jumped to 130 kt by 17 September, then weakened to 55 kt before reaching the Chinese coast south of Shanghai. Its rain killed seven people in Kyushu.

Vicki in Luzon and Japan, Yanni in Korea

Typhoon Vicki formed in the South China Sea and moved east, crossing western Luzon as an 85 kt typhoon. The JTWC cited reports of nine deaths and more than 300,000 people affected by flooding there. On 18 September, as Vicki churned nearby, the ferry Princess of the Orient sank near the mouth of Manila Bay with 430 people aboard, and dozens died. Vicki regained strength over the Philippine Sea and came ashore south of Osaka on 22 September at 90 kt. It killed 108 people along its path.

Typhoon Yanni peaked at 80 kt on 29 September, weakened as it passed over Cheju Island, and struck South Korea near Yeosu on 30 September as a 50 kt tropical storm. The JTWC cited a South Korean news agency report of 50 deaths and thousands of people forced from their homes.

Zeb and Babs: two super typhoons on Luzon in a week

Typhoon Zeb formed in the monsoon trough southeast of Guam in early October. As it strengthened, Guam's WSR-88D radar found a second cyclone forming in its inflow, which the JTWC warned on as Tropical Storm Alex before Zeb absorbed it. Zeb reached 155 kt and 900 hPa on 13 October in the archive, the season's strongest storm, and the JTWC places that peak just before it came ashore south of Palanan Bay on northern Luzon. It weakened over the island, passed 10 nm east of Taiwan and raced across all four main Japanese islands before becoming extratropical.

The JTWC reported 74 deaths on Luzon and 25 in Taiwan from Zeb. Later totals give 122 casualties along its path.

Typhoon Babs formed southeast of Guam a few days behind Zeb. An upper-level trough slowed it and pushed it south for 36 hours in the Philippine Sea, and once that trough filled, Babs reached 135 kt on 20 October off Mindanao. It crossed Catanduanes and the Polillo Islands and came ashore on central Luzon, where it weakened to 85 kt. News reports cited by the JTWC gave 156 deaths from mudslides and nearly 400,000 people displaced in the Philippines, and over 20 inches of rain in 24 hours in eastern Taiwan. Later totals give more than 300 deaths.

Weak storms, heavy floods in Vietnam

Late in the year the South China Sea produced a run of weak storms that caused outsized damage in Vietnam. Tropical Storm Chip reached 50 kt before weakening along the southern coast; its remnants crossed the Malay Peninsula and grew into a Bay of Bengal cyclone that struck Bangladesh, where the JTWC reported more than 100 fishermen lost. Tropical Storm Dawn came ashore near Cam Ranh on 19 November at 45 kt, and its floods killed at least 187 people and left about 2 million homeless. Tropical Storm Elvis struck north of Quy Nhon a week later, and the JTWC cited about 49 deaths and US$30 million of damage in Binh Dinh and Quang Ngai.

Typhoon Faith formed in the western Caroline Islands, reached typhoon strength over Samar on 10 December and peaked at 90 kt over the South China Sea. It weakened to a tropical storm before coming ashore near Cam Ranh on 14 December. The JTWC reported 29 deaths and over US$13 million of damage in the Philippines and at least 38 deaths and more than US$20 million of damage in Vietnam. The archive's last tropical-stage observation for the year comes on 22 December.

The warning center moves to Hawaii

The JTWC ran the 1998 season while leaving Guam for Pearl Harbor under base closure legislation. It split forecast watches between the two sites in November and December and completed the move by 1 January 1999, with about 90 percent of its staff turning over from June. The center also rated 1998 one of its hardest forecast years in two decades, measured against its climatology and persistence baseline model.