Severe Tropical Storm Chanthu, known in the Philippines as Tropical Storm Gener, was a strong tropical storm that produced deadly flooding in Indochina in mid June 2004. Originating from an

area of low pressure In meteorology, a low-pressure area (LPA), low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. It is the opposite of a high-pressure area. Low-pressure areas are commonly associated with inclem ...

on June 5, 2004, Chanthu was first declared a tropical depression near southern

Leyte Island Leyte ( ) is an island in the Visayas group of islands in the Philippines. It is eighth-largest and sixth-most populous island in the Philippines, with a total population of 2,626,970 as of 2020 census. Since the accessibility of land has been ...

in the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

. Tracking west-northwestward, the depression intensified into a tropical storm over the central Philippines before entering the

South China Sea The South China Sea is a marginal sea of the Western Pacific Ocean. It is bounded in the north by South China, in the west by the Indochinese Peninsula, in the east by the islands of Taiwan island, Taiwan and northwestern Philippines (mainly Luz ...

. Once over the warm waters of the sea, the system quickly intensified, attaining its peak 10-minute winds of 110 km/h (70 mph) and 1-minute winds of 140 km/h (85 mph). On June 12, the storm made

landfall Landfall is the event of a storm moving over land after being over water. More broadly, and in relation to human travel, it refers to 'the first land that is reached or seen at the end of a journey across the sea or through the air, or the fact ...

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

before quickly weakening over land. By June 13, the system had weakened to a tropical depression and dissipated two days later. In Vietnam, Chanthu wrought substantial damage and killed 38 people. Damage from the storm was estimated at 125 billion Vietnam dong (US$7.9 million), mostly from agricultural losses. One person was also killed in Thailand.

Meteorological history

Severe Tropical Storm Chanthu originated out of a weak

associated with disorganized deep convective activity located about 480 kilometres (300 mi) east-southeast of

Yap Yap (, sometimes written as , or ) traditionally refers to an island group located in the Caroline Islands of the western Pacific Ocean, a part of Yap State. The name "Yap" in recent years has come to also refer to the state within the Federate ...

on June 5. Low

wind shear Wind shear (; also written windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical ...

and weak diffluence allowed the system to gradually become organized; however, the following day, the

Joint Typhoon Warning Center The Joint Typhoon Warning Center (JTWC) is a joint United States Navy – United States Air Force command in Pearl Harbor, Hawaii. The JTWC is responsible for the issuing of tropical cyclone warnings in the North-West Pacific Ocean, South P ...

(JTWC) ceased monitoring the system for potential development. By June 7, convection redeveloped around the low and the JTWC resumed monitoring the low; later in the day, the

Japan Meteorological Agency The Japan Meteorological Agency (JMA; ''気象庁, Kishō-chō'') is a division of the Ministry of Land, Infrastructure, Transport and Tourism dedicated to the Scientific, scientific observation and research of natural phenomena. Headquartered ...

JMA, the

Regional Specialized Meteorological Center A Regional Specialized Meteorological Centre (RSMC) is responsible for the distribution of information, advisories, and warnings regarding the specific program they have a part of, agreed by consensus at the World Meteorological Organization as ...

for the western Pacific basin, classified it as a tropical depression. The same day, the depression entered the Area of Responsibility (AoR) of the

Philippine Atmospheric, Geophysical and Astronomical Services Administration The Philippine Atmospheric, Geophysical and Astronomical Services Administration (, abbreviated as PAGASA , which means "hope" as in the Tagalog word ''pag-asa'') is the National Meteorological and Hydrological Services (NMHS) agency of the P ...

and was given the local name ''Gener''. On June 8, the JTWC issued a

Tropical Cyclone Formation Alert A Tropical Cyclone Formation Alert (TCFA) is a bulletin released by the U.S. Navy-operated Joint Typhoon Warning Center in Honolulu, Hawaii or the Fleet Weather Center in Norfolk, Virginia, warning of the possibility of a tropical cyclone formi ...

for the system as they anticipated it to develop into a tropical storm within 24 hours. At 0000 UTC on June 9, the JTWC designated the depression as Tropical Storm 08W while located about 795 km (495 mi) southeast of

Manila, Philippines Manila, officially the City of Manila, is the capital and second-most populous city of the Philippines after Quezon City, with a population of 1,846,513 people in 2020. Located on the eastern shore of Manila Bay on the island of Luzon, it is ...

. Several hours later, the storm made landfall on southern

with winds of 55 km/h (35 mph 10-minute winds) according to the JMA and 75 km/h (45 mph 1-minute winds) according to the JTWC. Rapidly tracking towards the west-northwest in response to a

subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones immediately to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Ge ...

ridge A ridge is a long, narrow, elevated geomorphologic landform, structural feature, or a combination of both separated from the surrounding terrain by steep sides. The sides of a ridge slope away from a narrow top, the crest or ridgecrest, wi ...

to the north, the storm traversed the Philippine islands by June 10. Late on June 10, the JMA upgraded the system to a tropical storm, at which time it received the name ''Chanthu''; the name was contributed by

Cambodia Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...

and is a type of flower. Not long after being named, convection associated with the storm became displaced from the center of circulation, leaving the low pressure center partially exposed. As Chanthu neared Vietnam, it tracked over warm

sea surface temperature Sea surface temperature (or ocean surface temperature) is the ocean temperature, temperature of ocean water close to the surface. The exact meaning of ''surface'' varies in the literature and in practice. It is usually between and below the sea ...

s in the

, allowing the storm to quickly intensify. Outflow from the storm improved on June 11 and deep convection developed around the center of circulation. During a 12-hour span late on June 11 through early on June 12, the central

barometric pressure Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1,013.2 ...

of Chanthu dropped 15 hPa (mbar), falling to 975 hPa (mbar). The

maximum sustained wind The maximum sustained wind associated with a tropical cyclone is a common indicator of the intensity of the storm. Within a mature tropical cyclone, it is found within the eyewall at a certain distance from the center, known as the radius of ma ...

s also rose at this time; the JMA assessed the storm to have peaked with winds of 110 km/h (70 mph 10-minute winds) as a severe tropical storm; however, the JTWC assessed Chanthu to have peaked as a Category 1 typhoon on the Saffir–Simpson hurricane scale with winds of 140 km/h (85 mph 1-minute winds). Chanthu made

around 1200 UTC on June 12 near

Qui Nhơn Quy Nhon ( ) is a coastal city in Bình Định province in central Vietnam. It is composed of 16 wards and five communes with a total of . Quy Nhon was the capital of the former Bình Định province. As of 2022 its population was 481.110. H ...

, Vietnam, at this intensity. Due to the interaction with land, the storm rapidly weakened, with the JMA classifying it as a tropical depression early on June 13. The remnants of the storm persisted over

until June 15 at which time it dissipated.

Impact and aftermath

As a tropical storm, Chanthu passed through the

, producing moderate rainfall across several islands. The highest total was recorded at Roxas where of rain fell. In Vietnam, Chanthu dropped up to , triggering flooding that killed 38 people. At least 180 homes were completely destroyed and numerous others were damaged. Tens of thousands of hectares of agricultural land was inundated by the storm. Damage from the storm were estimated at 125 billion VND (US$7.9 million). In Thailand, the remnants of Chanthu produced widespread rainfall between June 13 and 16. Daily rainfall totals peaked at in

Nan, Thailand Nan (; , ) is a town in northern Thailand. It is north of Bangkok. It is in the centre of Nan province which bears its name, and of which it is the former administrative capital. It covers ''tambon'' Nai Wiang and parts of ''tambon'' Pha Sing ...

. Storm totals are not known but likely surpassed . Throughout the country, only one person perished as a result of the storm.International Disaster Database
Université Catholique de Louvain 2010. Retrieved May 30, 2010. Following the storm, the

Government of Vietnam The Government of the Socialist Republic of Vietnam (; less formally the Vietnamese Government or the Government of Vietnam, ) is the Cabinet (government), cabinet and the central Executive (government), executive arm of the Politics of Vietn ...

allocated 36 billion

Vietnamese đồng The dong (; ; ; sign: ₫ or informally đ and sometimes Đ in Vietnamese; code: VND) is the currency of Vietnam, in use since 3 May 1978. It is issued by the State Bank of Vietnam. The dong was also the currency of the predecessor states of ...

(US$2 million) in recovery funds. Twenty of the fatalities were from one ship which went missing during the storm, on June 24, search attempts were called off. The families of the fishermen were each given 10 million VND (US$560) in cash and gifts by National Assembly Deputy Chairman Truong Quang Duoc.

Meteorological history

Impact and aftermath

See also

References

External links