Typhoon Haiyan, known in the Philippines as Super Typhoon Yolanda, was an extremely powerful and catastrophic tropical cyclone that is among the most intense tropical cyclones ever recorded. Upon making landfall, Haiyan devastated portions of Southeast Asia, particularly the Philippines, during early November 2013. It is one of the deadliest typhoons on record in the Philippines, killing at least 6,300 people in the region of Visayas alone. It was the most intense and deadliest tropical cyclone worldwide in 2013.

The 30th named storm, thirteenth typhoon, and fifth super typhoon of the 2013 Pacific typhoon season, Haiyan originated from a low-pressure area several hundred kilometers east-southeast of Pohnpei in the Federated States of Micronesia on November 2. Tracking generally westward, environmental conditions favored tropical cyclogenesis and the system developed into a tropical depression on the following day. After becoming a tropical storm and receiving the name Haiyan at 00:00 UTC on November 4, 2013, the system began a period of rapid intensification that brought it to typhoon intensity by 18:00 UTC on November 5, 2013. By November 6, 2013, the Joint Typhoon Warning Center (JTWC) assessed the system as a Category 5-equivalent super typhoon on the Saffir–Simpson hurricane wind scale (SSHWS); the storm passed over the island of Kayangel in Palau shortly after attaining this strength.

The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) estimated the average ten-minute sustained winds at 235 km/h (146 mph) and gusts up to 275 km/h (171 mph) at landfall over Guiuan, Eastern Samar. Haiyan continued to intensify; at 12:00 UTC on November 7, 2013, the Japan Meteorological Agency (JMA) upgraded the storm's maximum ten-minute sustained winds to a peak of . The Hong Kong Observatory put the storm's maximum ten-minute sustained winds at prior to landfall in the central Philippines, while the China Meteorological Administration (CMA) estimated the maximum two-minute sustained winds at the time to be around 78 m/s or . At the same time, the JTWC estimated the system's one-minute sustained winds at , making Haiyan one of the strongest tropical cyclone ever observed based on wind speed.

At 20:40 UTC on November 7, 2013, the eye of the typhoon made its first landfall in the Philippines at Guiuan, Eastern Samar at maximum strength. Gradually weakening, the storm made five additional landfalls in the country before emerging over the South China Sea. Turning northwestward, the typhoon eventually struck northern Vietnam as a severe tropical storm on November 10, 2013. Haiyan was last noted as a tropical depression by the JMA on the following day.

The first warning noted for Haiyan was in November 3, 2013, when a storm warning arose in the Federated States of Micronesia, specifically in the Chuuk Lagoon, Losap, and Poluwat, gradually expanding to other towns as well. Warnings rose for a second time in Micronesia, before being discontinued. In the Philippines, PAGASA raised Signal No. 1 on November 6, before the landfall of Haiyan. More provinces were included, until Signal No. 4, the highest warning, was raised. Other preparations were made, such as class suspensions and evacuations. In China, an emergency was declared in three provinces, causing vessels to be brought back to shore. In Vietnam, the highest emergency level was announced, causing thousands of people to be evacuated.

In Micronesia, heavy rains scattered in most of the places, causing one canoe house and three other houses to be destroyed. Other than houses, many trees were downed. In Palau, houses were also destroyed. Power outages were reported, with a total of 69 people being displaced. In Taiwan, eight people died due to strong waves. One person was also declared missing in Hong Kong. In Southern China, extensive flooding occurred, killing 30 people and destroying 900 homes. In Vietnam, heavy rains battered the country, killing 18 people and injuring 93.

The typhoon caused catastrophic destruction in the Visayas, particularly on the islands of Samar and Leyte. According to UN officials, about 11 million people were affected and many were left homeless; many people are still missing as a result of this storm. People are still affected today from housing issues and homelessness, and the economy is still affected.

Due to its extensive deaths and damage, the name Haiyan was retired in 2014 and replaced with Bailu. It was first used in the 2019 season.

Meteorological history

On November 2, the Joint Typhoon Warning Center (JTWC) began monitoring a broad low-pressure area about east-southeast of Pohnpei, one of the states in the Federated States of Micronesia. As the system moved through a region favoring tropical cyclogenesis, the Japan Meteorological Agency (JMA) classified it as a tropical depression early on November 3.

The system quickly intensified into a tropical storm, prompting the JMA to assign it the name Haiyan at 00:00 UTC on November 4. Tracking generally westward along the southern periphery of a subtropical ridge, rapid intensification ensued by November 5 as a central dense overcast with an embedded eye developing; the JMA classified Haiyan as a typhoon later that day. On November 6, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) assigned the storm the local name Yolanda as it approached the Philippine Area of Responsibility.

Intensification slowed somewhat during the day, though the JTWC estimated the storm to have attained Category 5-equivalent super typhoon status on the Saffir–Simpson hurricane wind scale (SSHWS) around 12:00 UTC. Later, the eye of the typhoon passed over the island of Kayangel in Palau.

Around 12:00 UTC on November 7, Haiyan attained ten-minute sustained winds of and a minimum central pressure of 895 mbar (hPa; ). Six hours later, the JTWC estimated Haiyan to have attained one-minute sustained winds of and gusts up to . The storm displayed some characteristics of an annular tropical cyclone, though a strong convective band remained present along the western side of the system.

At 20:40 UTC on November 7, Haiyan made landfall in Guiuan, Eastern Samar at peak intensity. The JTWC's own estimate of one-minute sustained winds of would, by that measure, make Haiyan the most powerful storm ever recorded to strike land. This record was later broken by Typhoon Goni in 2020. Interaction with land caused a slight degradation of the storm's structure, though it remained an exceptionally-powerful storm when it struck Tolosa, Leyte around 23:00 UTC. The typhoon made four additional landfalls as it traversed the Visayas: Daanbantayan and Bantayan Island in Cebu, Concepcion in Iloilo, and Busuanga Island in Palawan.

Haiyan, with its core disrupted by land interaction with the Philippines, emerged over the South China Sea late on November 8. Environmental conditions ahead of the storm soon became less favorable, as cool stable air began wrapping into the western side of the storm's circulation. Continuing across the South China Sea, Haiyan turned more northwesterly late on November 9 and through November 10, as it moved around the southwestern edge of the subtropical ridge previously steering it westward. Rapid weakening ensued as Haiyan approached its final landfall in Vietnam, ultimately moving ashore in the country near Haiphong around 21:00 UTC, as a severe tropical storm. Once onshore, the storm quickly deteriorated and was last noted as it dissipated over Guangxi Zhuang Autonomous Region, China, on November 11.

Preparations Micronesia and Palau Upon JTWC's declaration of Tropical Depression 31W on November 3, a tropical storm warning was issued for Chuuk Lagoon, Losap, and Poluwat in the Federated States of Micronesia. Further west, Faraulep, Satawal, and Woleai, were placed under a typhoon watch while Fananu and Ulul were placed under a tropical storm watch. The following day, the tropical storm warning expanded to include Satawal while a typhoon warning was issued for Woleai. Much of Yap State and the islands of Koror and Kayangel in Palau were placed under a typhoon watch. The government issued a mandatory evacuation for Kayangel, and although most residents ignored the warning, they all survived the storm. As Haiyan progressed westward, the easternmost advisories were gradually discontinued. As Haiyan intensified into a typhoon on November 5, warnings were raised across Palau and Yap State. Government offices in Melekeok were used as an evacuation building for Palau. Despite mandatory evacuation orders, most residents on Kayangel remained on the island and rode out the typhoon.

Philippines

Shortly before Haiyan entered the Philippine Area of Responsibility on November 6, PAGASA raised Public Storm Warning Signal (PSWS) No.1, the lowest of four levels, for much of the Visayas and Mindanao. As the storm continued to approach the country, warnings expanded into Luzon and increased in severity for eastern areas. By the evening of November 7, PSWS No. 4, the highest level of warning which indicates winds in excess of are expected, was raised for Biliran Island, Eastern Samar, Leyte, Northern Cebu, Metro Cebu, Samar, and Southern Leyte. Through November 8, the coverage of PSWS No. 4 continued to expand, with areas in southern Luzon being included.

Officials placed police officers in the Bicol Region ahead of the storm. In the provinces of Samar and Leyte, classes were canceled, and residents in flood- and landslide-prone areas were required to evacuate. Some of the storm-threatened areas were affected by an earlier earthquake in Bohol. Then-Philippine President Noynoy Aquino requested the military to deploy planes and helicopters to the region expected to be affected. As Haiyan was moving very fast, PAGASA issued warnings at different levels to about 60 of the 80 provinces, including the capital Metro Manila. On November 8, the International Charter on Space and Major Disasters was activated, providing widespread charitable satellite coverage to relief organizations.

Southern China The State Flood Control and Drought Relief Headquarters hoisted a level three emergency response in the provinces of Hainan, Guangdong and Guangxi. All fishing vessels were urged to return to ports by noon on November 9. The Hong Kong Observatory issued the Strong Monsoon Signal at 19:10 HKT on November 9, and it was still in place on November 13.

Vietnam On November 8, Prime Minister Nguyễn Tấn Dũng activated the highest state of preparedness in the country. Approximately 600,000 people across southern and central provinces were evacuated while a further 200,000 were evacuated in northern provinces. Alerts were sent to 85,328 seagoing vessels, with a collective crew of 385,372 people, to sail to safer waters away from the storm. Requests were sent to China, Malaysia, Indonesia, and the Philippines to aid any fishermen who needed immediate shelter from the typhoon. Threatening Vietnam after two other typhoons, Wutip and Nari, there were concerns that the storm would cause significant damage to homes with makeshift repairs. Roughly 460,000 military personnel and other authorities were mobilized to assist in evacuation efforts. Hundreds of flights were canceled across the country while schools were closed on November 11. On the small island of Cồn Cỏ, all residents were moved to underground shelters with enough supplies for several days. The International Federation of Red Cross and Red Crescent Societies (IFRC) branches in Vietnam prepared relief stockpiles, consisting of food, water, housing material, and ₫6.6 billion (US$310,000) in funds. The local United Nations Resident Coordinator, Pratibha Mehta, praised the government's actions and credited them with saving numerous lives. However, there were complaints from many residents that the warnings came too late.

Impact