2012 Pacific typhoon season

Season overview

By the Joint Typhoon Warning Center's own tally, 2012 was a slightly below average year in the western North Pacific, with 27 cyclones warned on against a long-term average of 31. Conditions were close to neutral in the El Niño Southern Oscillation, and storm formation shifted east compared with 2011. Many systems followed looping, S-shaped or erratic paths, particularly over the Philippine Sea and the South China Sea.

Forecasters had expected a quiet first half as the lingering La Niña held back the monsoon trough, and early forecasts from the Tropical Storm Risk consortium called for activity slightly below normal. As sea surface temperatures warmed through the summer, the consortium raised its outlook in July and August to an above average season. The archive records accumulated cyclone energy of 300.4 for the year, driven largely by a handful of long-lived, intense typhoons.

How the season unfolded

The archive's first system was a weak depression east of the Philippines in mid-February. Tropical Storm Pakhar followed in late March in the South China Sea and came ashore in southern Vietnam on April 1. Typhoon Sanvu became the season's first typhoon on May 24 while crossing the open ocean north of Guam, and passed directly over Iwo Jima before weakening.

June brought Typhoon Mawar, which recurved east of the Philippines, and Typhoon Guchol, which rapidly intensified into a 130-knot storm in the Philippine Sea before weakening and reaching Japan's Kii Peninsula as a tropical storm on June 19. Tropical Storm Talim and Tropical Storm Doksuri were short-lived systems that ended over southern China.

The busiest stretch ran from mid-July to the end of August. Tropical Storm Khanun crossed Jeju and the Korean Peninsula, Typhoon Vicente struck Guangdong, and Typhoon Saola, Typhoon Damrey and Typhoon Haikui formed within days of each other in late July and early August, all ending in mainland China. Typhoon Kai-Tak hit the Leizhou Peninsula and northern Vietnam in mid-August, while Typhoon Tembin and Typhoon Bolaven developed side by side. Tembin looped counterclockwise off southern Taiwan, affecting the island twice, before turning north to South Korea.

Typhoon Sanba and Typhoon Jelawat dominated September, both reaching Category 5 strength in the Philippine Sea before turning north. October was quieter but long-running: Typhoon Prapiroon wandered for two weeks east of Taiwan and has the longest record of the year in the archive, from October 5 to October 23. Tropical Storm Gaemi drifted in the South China Sea before reaching Vietnam, and its remnants helped seed a depression in the Bay of Bengal. Typhoon Son-Tinh crossed the central Philippines and then strengthened over the South China Sea before affecting Hainan and northern Vietnam late in the month.

After a weak depression in November, Typhoon Bopha formed at a very low latitude near 3 degrees north on November 25 and lasted into December. Tropical Storm Wukong closed the season, crossing the Visayas over Christmas and dissipating south of Vietnam on December 29.

Strongest storms

Typhoon Sanba was the most intense storm of the year. It intensified explosively east of the Philippines and reached a peak of 155 knots with a minimum pressure of 907 hPa on September 13, the strongest in the basin since 2010. An eyewall replacement then produced a very large eye, and Sanba weakened steadily as it moved north past Okinawa to South Korea.

Typhoon Bopha peaked at 150 knots and 911 hPa on December 3, just before striking Mindanao, and briefly regained major typhoon strength over the South China Sea several days later. Typhoon Jelawat, the third Category 5 storm, reached 140 knots on September 24 after developing a small eye, and held much of that strength for about two days before two eyewall replacements and cooler water weakened it.

Below them came four Category 4 typhoons: Guchol at 130 knots in June, Bolaven at 125 knots in August, Tembin at 120 knots and Vicente at 115 knots. Vicente's strengthening was the most abrupt: explosive intensification on July 23 carried it to Category 4 within hours of becoming a typhoon, just before landfall in Guangdong. Mawar, Prapiroon and Son-Tinh completed the list of major typhoons, each peaking at 105 knots.

Notable landfalls and impacts

Okinawa bore the brunt of the late-summer storms. The Joint Typhoon Warning Center counted three direct hits between late August and late September, by Typhoon Bolaven, Typhoon Sanba and Typhoon Jelawat, and five further passages within 150 miles. Jelawat went on to make landfall in Aichi Prefecture on Honshu on September 30, and Sanba brought heavy rain and crop losses to both Japan and South Korea.

Typhoon Bolaven was the most damaging storm to reach the Korean Peninsula. It passed over Okinawa on August 26 and made landfall in North Korea on August 28. Wikipedia's season table lists 96 deaths across China, Japan and Korea, including at least 59 in North Korea and 19 in South Korea, and total damage of about US$3.77 billion in 2012 dollars. Earlier, Tropical Storm Khanun had fed severe flooding in North Korea, where the government reported 88 deaths.

Mainland China took a series of blows. Typhoon Vicente prompted Hong Kong's highest warning, Hurricane Signal No. 10, for the first time since 1999, before landfall at Taishan. Typhoon Damrey became the most intense tropical cyclone to make landfall north of the Yangtze River since 1949, reaching Jiangsu on August 2. Typhoon Haikui struck Zhejiang days later and, although its centre stayed far from the Philippines, was linked to at least 89 deaths there. The season table credits Haikui with 118 deaths and about US$5.9 billion in damage, and Typhoon Saola, which looped over Taiwan before reaching China, with 85 deaths and about US$2.7 billion, all in 2012 dollars and including precursor and remnant effects.

Typhoon Bopha was the season's deadliest storm. Known locally as Pablo, it made landfall in eastern Mindanao at Category 5 strength, triggering landslides and destroying homes across a region that rarely sees typhoons. The season table lists 1,901 deaths and about US$1.16 billion in damage in 2012 dollars, and Bopha is the main reason the season is remembered as a deadly one. Earlier in the year, Typhoon Son-Tinh killed 27 people in the Philippines, and Tropical Storm Wukong killed 23 there just after Christmas.

Counts, definitions and names

Agency tallies differ because they measure winds differently. The site counts storms using US-agency one-minute winds, giving 25 tropical storms and 15 typhoons. The Japan Meteorological Agency, which uses ten-minute winds, also named 25 tropical storms but classed 14 as typhoons. The Joint Typhoon Warning Center counted four super typhoons, using a 130-knot threshold that includes Guchol, whereas Category 5 on the one-minute scale begins at 137 knots, which gives the site's three.

Six names, including Pakhar, Sanba and Son-Tinh, were used for the first time in 2012 as replacements for names retired after earlier seasons. After the season, the Typhoon Committee retired Vicente and Bopha, and the Philippine weather agency retired Pablo, the local name for Bopha.