Typhoon Yutu

Typhoon Yutu, known in the Philippines as Typhoon Rosita, was an extremely powerful tropical cyclone that caused catastrophic destruction on the islands of Tinian and Saipan in the Northern Mariana Islands, and later impacted the Philippines. It is the strongest typhoon ever recorded to impact the Mariana Islands, and is tied as the second-strongest tropical cyclone to strike the United States and its unincorporated territories by both wind speed and barometric pressure. It also tied Typhoon Kong-rey as the most powerful tropical cyclone worldwide in 2018.

The twenty-sixth named storm and the twelfth typhoon of the 2018 Pacific typhoon season, Yutu originated as a tropical disturbance moving westward on October 18. It became a tropical depression two days later near the Marshall Islands, before strengthening further into a tropical storm on October 22, receiving the name ''Yutu'' from the Japan Meteorological Agency (JMA). Favorable conditions led to a period of rapid intensification, causing Yutu to become a typhoon as it moved west-northwestward on October 23, and by the next day, Yutu had achieved its peak intensity; the JMA estimated 10-minute maximum sustained winds of and a lowest central pressure of , while the Joint Typhoon Warning Center assessed 1-minute winds of . An eyewall replacement cycle ensued, weakening Yutu, before making landfall over Tinian on October 25. Substantial outflow allowed the storm to re-strengthen, making it reach a secondary peak on October 26. As it approached the Philippines the following day, PAGASA assigned it the local name ''Rosita'', while it began to reach less favorable conditions. The storm made a second landfall over Dinapigue, Isabela by October 29. Yutu then entered the South China Sea, where it continued to weaken while turning northward, until it had dissipated by November 3.

An emergency was declared for the Northern Mariana Islands as Yutu approached the archipelago, while tropical cyclone warnings and watches were raised. Winds of and gusts of swept across Tinian and Saipan, causing devastating damage throughout the Northern Mariana Islands that amounted over , far exceeding that of Typhoon Soudelor in 2015. The storm destroyed up to 6,000 homes and toppled 962 power poles in Saipan and Tinian, leaving the islands without power for months. Health centers and airports in the two islands sustained serious damage. Two women were killed in Saipan and 121–133 people were injured. Yutu caused power outages to Rota and Guam, with damage to the latter island estimated at US$750,000. In response to the disaster, a major disaster declaration from U.S. President Donald Trump was signed; the Northern Mariana Islands received aid from organizations and local and federal governments.

Tropical Cyclone Wind Signals were issued throughout Luzon while the Philippines was still recovering from Typhoon Mangkhut, leading to pre-emptive evacuation of 32,519 people. Yutu brought rainfall of on the island, flooding low-lying areas. Yutu affected 567,691 people across the nation, displacing a majority of them after damaging 66,165 homes. The storm killed 32 people in the country, 21 of which died in Natonin from one of at least eleven landslides, and also injured two. Power outages occurred across Luzon, with most of it restored by October 31. Agricultural damage in the Philippines amounted to ₱2.904 billion (US$55.160 million). Elsewhere, a man in Hong Kong died while surfing in high waves as a typhoon signal was hoisted.

Meteorological history

Typhoon Yutu originated on October 18, 2018, from an area of atmospheric convection, or thunderstorms, near . Having an unorganized center with scattered convection, the tropical disturbance situated around warm waters of and low vertical wind shear, acquiring dual outflow channels aloft—all of which aided in development. Moving westward during October 20, the system received excellent equatorward outflow, while intense convection wrapped into its elongated center. By 18:00 UTC, the JMA reported that the disturbance had intensified into a tropical depression near the Marshall Islands. Eighteen hours later on October 21, the United States Joint Typhoon Warning Center (JTWC) designated the consolidating system ''31W''. A subtropical ridge to the southwest steered the storm west-northwestward, towards the Mariana Islands. Radial outflow was limited by a weak tropical upper tropospheric trough (TUTT) cell to the northwest, though the cell soon diminished the next day. At 00:00 UTC, both the JMA and JTWC classified the system a tropical storm, with the former assigning it the name ''Yutu''.

Yutu expanded in size, with the strongest convection to the east and south of the center; an intense rainband to the south later developed, marking the beginning of a period of explosive intensification. Deep convection bloomed, obscuring the center and significantly improving its structure with substantial poleward and radial outflow. At 18:00 UTC, the JMA upgraded Yutu to a severe tropical storm, and six hours later on October 23, both the JMA and JTWC classified the storm a typhoon. A pinhole eye began to develop, becoming apparent on satellite imagery, with banding features continuously tightening towards the center. A large area of intense thunderstorms persisted to the north of the center, as very favorable conditions fueled the typhoon. Over a region of high ocean heat content, the eye became well-defined and expanded to . Although it soon contracted to , by 00:00 UTC of October 24, Yutu was classified a super typhoon by the JTWC. The eye became wide, with extremely deep convective bands to the north and south of it. By 12:00 UTC, the JMA and JTWC reported that Yutu had attained its peak intensity; the former estimated 10-minute maximum sustained winds of and a barometric pressure of , and the latter estimated 1-minute winds of , making Yutu equivalent to a Category 5 hurricane on the Saffir–Simpson scale. Operationally, the JTWC estimated winds of —based on Dvorak estimates of T7.5, which utilized satellite appearance to determine intensity.

Between 14:00 UTC and 18:00 UTC (00:00 ChST and 04:00 ChST of October 25), Yutu struck Tinian and the southern portion of Saipan at peak intensity, becoming the most powerful storm on record to impact the Northern Mariana Islands, surpassing Typhoon Soudelor in 2015. Additionally, the JTWC reported a lowest central pressure of at 18:00 UTC. After striking the Mariana Islands, cold cloud tops began to warm, signaling a weakening trend. Furthermore, microwave imagery revealed concentric eyewalls, indicating the onset of an eyewall replacement cycle. During the process, the eastern periphery of the eyewall thinned under the influence of dry air in the middle troposphere, as wind shear became moderate during October 25. The primary eyewall then eroded, as an anticyclone east of the storm obstructed outflow. The cycle was then completed, evident by a Special Sensor Microwave Imager/Sounder image. Yutu was more asymmetric, with its movement influenced by the subtropical ridge to the north and a large, weak mid-latitude shortwave trough associated with it. During October 26, the eye again became well-defined and expanded to , as low easterly wind shear and excellent outflow persisted despite the anticyclone. Convection near the center became symmetrical, cloud tops cooled, and the eye contracted and became cloud-filled. The eye then sharpened and became wide as convective bands wrapped very tightly into the intense center. By 18:00 UTC, the JMA and the JTWC reported that Yutu had attained its secondary peak intensity; the JMA estimated winds of and a minimum barometric pressure of , and the JTWC gave Yutu the same wind estimate as the previous peak.

Over the Philippine Sea, Yutu crossed the 135° E boundary of the Philippine Area of Responsibility (PAR) at 00:00 UTC of October 27, receiving the local name ''Rosita'' from the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA). Cloud tops reached as Yutu remained over warm waters, steering westward, though the eye became ragged. Yutu then briefly entered a region of high vertical wind shear, weakening the storm. The eye enlarged further to on October 28, though poleward outflow weakened. Intense thunderstorms eroded off the eastern edge of Yutu from dry air, which wrapped into the storm's circulation from the west, with cloud tops warming and the eye contracting; on this basis, the JTWC assessed that Yutu had weakened to below super typhoon strength at 12:00 UTC. Sea surface temperatures had also decreased in the cold wakes of previous Typhoons Mangkhut, Trami, and Kong-rey advected by the North Equatorial Current, contributing to the degrading of Yutu. While approaching Luzon, rainbands began to collapse, after outflow had reduced. Meanwhile, Yutu steered west-southwestward along the southern edge of the subtropical ridge. During October 29, the eye became ill-defined and cloud-filled, with most convection in the southern eyewall and limited in the northern part of it. Between 20:00 UTC and 21:00 UTC, Yutu made landfall over Dinapigue, Isabela, Philippines, with winds of estimated by PAGASA. The JTWC, however, reported that Yutu had made landfall at 19:50 UTC. The storm continued to rapidly decay tracking westward inland over the next day. Despite this, the system still remained organized as it began to emerge over the South China Sea, though it weakened into a severe tropical storm at 06:00 UTC according to the JMA.

Moving away from the Philippines, Yutu re-consolidated from improved banding over the northern flank, but weakened into a tropical storm at 18:00 UTC, according to the JTWC. Rainbands were limited to the north and south quadrants of the storm during October 31. At 06:00 UTC, the JMA downgraded Yutu to a tropical storm. Meanwhile, the storm left the PAR at 08:00 UTC. Exhibiting a partially-exposed center, Yutu turned northwestward along the subtropical ridge. Regardless, the system stockpiled convection over its southern quadrant. Moreover, moderate wind shear was subdued by strong poleward outflow, making conditions favorable for intensification. By November 1, Yutu had briefly strengthened to near typhoon-force winds of , according to the JTWC. However, Yutu began experiencing moderate to high wind shear turning northward, limiting outflow and displacing deep convection to the northeast of the poorly-defined center. By November 2, the JMA reported that Yutu had weakened into a tropical depression at 06:00 UTC; the JTWC followed suit in downgrading the system six hours later. After the storm had lost all of its convection from unfavorable wind shear while southeast of Hong Kong, the JTWC reported that Yutu had degenerated into a tropical disturbance at 18:00 UTC, whereas the JMA continued monitoring the system until it had dissipated on November 3 at 06:00 UTC.

Preparations

Mariana Islands

On October 20, the National Weather Service (NWS) office in Tiyan, Guam released a Special Weather Statement on the pre-Yutu disturbance after a Tropical Cyclone Formation Alert from the JTWC was issued, stating that it could impact the Mariana Islands by midweek. Two days later, the NWS instated a tropical storm watch for Rota and a typhoon watch on Saipan and Tinian. As Tropical Storm Yutu continued towards the archipelago, tropical storm watches were added on Guam, Alamagan, Pagan, and Agrihan. With forecasts stating that Yutu would become a typhoon, the watches for Saipan and Tinian were upgraded to warnings on October 23; all tropical storm watches were upgraded to warnings later that day, and the typhoon watch for Rota was upgraded to a warning also. After Yutu had made landfall, all warnings and watches were canceled on October 25 as it moved away. In the month prior to Yutu, Typhoon Mangkhut struck the Mariana Islands, prompting emergency officials to stockpile supplies. With relief supplies largely unused, storage facilities on Guam had 220,000 liters of water and 260,000 meals readily available.

Condition of Readiness (COR) 2 was hoisted in Rota, Saipan, and Tinian on October 23, before it was upgraded to COR 1 the next day after Yutu had become a super typhoon. Governor Ralph Torres ordered all government offices to shut down in preparation of Yutu. Additionally, Northern Marianas College campuses were closed on October 23. The Chief Judge of the District Court, Ramona Villagomez Manglona, closed the federal court. Attorney General Edward Manibusan warned retailers against price gouging. Public schools canceled classes across the three main islands. Seven were used as shelter to accommodate 326 people; some of them were filled quickly. Hundreds of cars lined up at gas stations. U.S. President Donald Trump declared an emergency for the Northern Islands on October 24, which allowed the Federal Emergency Management Agency (FEMA) to deploy personnel to both Tinian and Saipan ahead of the storm. The Department of Fire and Emergency Medical Services in Saipan deployed a team in preparations. All flights in the Northern Marianas were canceled, though the Saipan International Airport remained open. The Commonwealth Utilities Corp. shut its water distribution system to conserve water tanks. Several businesses were closed, hotel constructions were suspended, and banks, restaurants, and other shops were boarded. Imperial Pacific suspended its casino. The United States Postal Service closed its offices in Saipan and Rota. United States Coast Guard ports were closed across Saipan, Tinian, Rota, and also Guam.

COR 2 was also hoisted in Guam, before it was upgraded to COR 1. People were encouraged to price gouging to the Office of the island's Attorney General. Governor Eddie Baza Calvo declared a state of emergency in anticipation of the typhoon. The Guam Department of Education closed all of its schools, with eight of them turned into emergency shelters to accommodate nearly 2,200 people. Catholic schools and charter schools were closed as well. St. John's School, the University of Guam, Guam Community College, and Harvest Christian Academy were also closed. The Guam Regional Transit Authority halted bus operations in response to the COR 2, and transit services were paused until two hours after COR 4—the normal Condition of Readiness. Banks were closed across the island, along with post offices, and all government agencies. The Legislature, Judiciary, and District Court were all closed as well. Guam Memorial Hospital, Guam Regional Medical City, and Naval Hospital Guam suspended all operations. Two Lovers Point and the War in the Pacific National Historical Park were closed. Flights to and from Antonio B. Won Pat International Airport were canceled.

Philippines

On October 27, after Yutu (Rosita) had entered the Philippine Area of Responsibility, the PAGASA issued gale warnings across the northern and eastern seaboards of Luzon and the eastern seaboard of the Visayas, due to the enhancement of the northeast monsoon by Yutu, which could also bring light rain over Batanes, the Babuyan Islands, the Ilocos Region, the Cordillera Administrative Region (CAR), and Cagayan Valley. The agency also advised fishermen and others with small vessels to not sail in those areas, while those with larger vessels were advised to look out for big waves. Starting October 28, PAGASA began releasing Tropical Cyclone Wind Signals (TCWS) across regions of the Philippines; TCWS No. 1 was raised across 23 areas or provinces in the Northern Philippines. Over the following days, TCWS No. 1 would span from the southern tip of Quezon to Batanes. On October 29, TCWS No. 2 was hoisted across Cagayan, Isabela, Aurora, Quirino, and Polillo Island, before it extended to Mountain Province, Ifugao, Benguet, and Nueva Vizcaya that same day. The signals for Isabela, Quirino, and the northern part of Aurora were raised to TCWS No. 3 along with Nueva Vizcaya and Ifugao. TCWS No. 3 was then raised across Benguet, La Union, Ilocos Sur, Mountain Province, and Pangasinan. An orange rainfall warning was issued across Bataan, Bulacan, Nueva Ecija, and Rizal, and extended to Pampanga, after Yutu had made landfall. After Yutu had cross Luzon by October 31, PAGASA no longer placed areas under warning signals.

About 155,242 people had moved to 1,388 evacuation centers. 593 cities or municipalities across Ilocos Region, Cagayan Valley, Central Luzon, Calabarzon, the Bicol Region, CAR, and Metro Manila had classes suspended, and 193 across Ilocos, Cagayan Valley, and CAR suspended government work. 44 flights were canceled, with 38 domestic and 6 international. 2,267 passengers and 217 sea vessels were stranded while sheltering in the ports. The Department of Social Welfare and Development had stockpiled 376,330 family food packages and relief items worth ₱919.672 million (US$17.463 million). Yutu was anticipated to produced similar effects of Typhoon Mangkhut (Ompong), which had devastated the country in September. While President Rodrigo Duterte visited areas previously affected by Mangkhut ahead of Yutu, he received complaints from local government unit officials that the Commission on Audit did not allow cash advancements for the procurement of building materials intended for the victims of Mangkhut.

Hong Kong

The Hong Kong Observatory (HKO) hoisted a No. 1 Standby Signal on October 31 as Yutu was southeast of the region. The next day while it was southeast, the agency raised a No. 3 Strong Wind Signal, the first in November since Typhoon Ira in 1993. As it weakened however, the signal was lowered to No. 1 on November 2, and was later canceled that same day.

Impact

Mariana Islands

Striking Tinian and Saipan on October 24 as a Category 5-equivalent super typhoon, Yutu became the strongest tropical cyclone to ever impact the Mariana Islands and the second-strongest to strike the United States or its territories as a whole, tied with Typhoon Karen in 1962 and Hurricane Camille in 1969. Only the 1935 Labor Day hurricane impacted the country at a greater strength. Yutu was the strongest and worst storm to impact the Marianas since Typhoon Jean in 1968. Meteorologist Brandon Aydlett at the NWS described the typhoon as "the storm which sets the scale for which future storms are compared to". Total damage in the Northern Mariana Islands was estimated to reach over $800 million, according to FEMA. Based on a joint study by the Guam NWS office and the University of Guam, maximum sustained winds of with wind gusts of swept the two islands. The highest wind gust was recorded at over Saipan at 14:44 UTC on October 24, before weather instruments across the island along with Tinian were damaged or destroyed. A resident recorded gusts of and an anemometer recorded a peak wind of . Though of rain was observed at Saipan International Airport, it was likely well below the actual rainfall. A rain gauge measured of rain, though it was northeast of Yutu's eye.

During the passage of Yutu, 121–133 people were injured. The typhoon killed two people in Saipan: a 44-year-old woman in Chalan Kanoa when it wrecked the building she was staying in, and another woman in Susupe who died of carbon monoxide poisoning caused by inhaling the fumes of a generator. Two antenna farms from the U.S. Agency for Global Media were torn apart by the intense winds. Satellite dishes that downlinked Radio Free Asia and Voice of America were either fragmented or removed entirely. The power plants of Saipan and Tinian were destroyed. The entirety of both islands were left without electricity; around 200 to 300 power poles were downed, 400 to 500 were leaning, and a large amount of transformers and conductors were downed as well. Some people were injured by glass and other debris. By the time the storm had passed, there were 779 downed poles in Saipan and 183 in Tinian. Maximum coastal flooding in Saipan and Tinian were measured at and respectively. Across the commonwealth, utility infrastructure was severely impacted. By November 5, Governor Ralph Torres stated that over 3,000 homes were destroyed, leaving thousands homeless, while the American Red Cross reported that as many as 6,000 homes were destroyed and 12,000 were affected. Cell towers were significantly damaged as well. Roads were inaccessible due to debris, in addition to ports. In total, seven public schools in Saipan and Tinian were severely damaged. The population of forest birds such as the golden white-eye, bridled white-eye, Mariana kingfisher, rufous fantail, and honeyeaters, was expected to decline as a result of the storm.

The majority of buildings in southern Saipan lost their roofs or were destroyed, including Hopwood Middle School, which suffered extensive damage, and the gymnasium and classrooms of Northern Marianas College. Yutu's eyewall also knocked out Saipan's doppler weather radar on October 25, during the storm's landfall. Cars were crushed under a collapsed garage in Saipan. Four hotels were closed after sustaining significant damage. Low-lying vegetation in southern parts of the island were shredded or ripped from the ground. The Joeten-Kiyu Public Library was flooded after its roof got damaged. Saipan International Airport sustained significant damage; terminals flooded and navigation aids were rendered inoperable. 462 homes were completely destroyed and 317 were severely damaged across Kagman, Lau Lau, Susupe, Chalan Kanoa, San Antonio, Koblerville, Dandan, and San Vicente. Many cars had their windshield and windows shattered by debris. Powerful winds dragged a container and crashed it into two police cars behind the Department of Public Safety building in Susupe. Additionally, many trees were uprooted.

One person was injured in Tinian. The majority of homes on Tinian were severely damaged or destroyed. Some concrete structures sustained significant damage, with a few completely destroyed, and residents reported that those buildings shook during the typhoon. Storm shutters were torn from windows, leaving the interior of structures exposed to wind and water damage. In one instance, a door was ripped from a building and hurled into a pigsty. The island's only health center sustained major damage; however, no patients were being treated at the time. The hospital's windows and doors were damaged, and the building was inundated. Tinian International Airport suffered significant damage. Emergency responders rescued 30 people. In total, 70 homes were destroyed and 113 were severely damaged across the villages of San Jose, the House of Taga, Carolinas, Marpo Valley and Marpo Heights. In San Jose, some generators whirred among flattened buildings, trees were uprooted, road signs were twisted, and laundry shook in crumpled homes. Its church was also totaled by the storm.

Yutu brought typhoon-force winds over Rota, causing property and crop damage of $1 million each. The island was without power with over 50 downed power poles severely damaged or destroyed, and 13 homes were destroyed and 38 were damaged across Songsong and Sinapalo. Rota Airport received debris along its runway. Guam endured tropical storm winds of . On October 25, Andersen Air Force Base recorded a gust of , while the NWS office recorded a peak gust of . The highest rainfall from Yutu in Guam was recorded in Dededo at . Yutu caused property damage of $500,000 to the island, while crop damage was estimated at $250,000. The Guam Power Authority

HOME


Content is Copyleft
Website design, code, and AI is Copyrighted (c) 2014-2017 by Stephen Payne


Consider donating to Wikimedia



As an Amazon Associate I earn from qualifying purchases