Typhoon Krathon, known in the Philippines as Super Typhoon Julian, was a powerful and erratic typhoon which impacted Taiwan and the Philippines in late-September and early-October 2024. Krathon was the first storm to make landfall on Taiwan's densely populated western plains since Typhoon Thelma in 1977. It was also the first storm to hit Kaohsiung in October and the first since Tropical Storm Trami in 2001 to weaken into a tropical depression over Taiwan. Additionally, it was also the strongest typhoon to hit Batanes since Typhoon Chanthu in 2021.
The twenty-sixth tropical depression, eighteenth named storm, second violent typhoon, and second super typhoon of the season, Krathon developed into a tropical depression near Kadena Air Base, Japan, on September 26. It became a tropical storm on September 28 and reached typhoon strength on September 29 after developing a broad, ragged eye. Krathon moved north-northwestward before shifting west-northwestward and passing near Sabtang, Batanes. On October 1, it reached peak intensity with ten-minute sustained winds of and a central pressure of , making it a Category 4-equivalent super typhoon on the Saffir-Simpson scale. After entering the northern South China Sea, an eyewall replacement cycle weakened the storm. Krathon made landfall near Siaogang District in Kaohsiung, Taiwan, on October 3, then rapidly weakened while moving through central Taiwan, near the western edge of the Central Mountain Range. The JMA monitored the system over the South China Sea before it dissipated later that day.
Ahead of the storm, a Tropical Cyclone Wind Signal was issued for various areas in the Philippines, with a red alert for Calayan and Santa Ana in Cagayan. Krathon resulted in at least five deaths, three people missing, and eight injured in the Philippines. Additionally, it was the wettest tropical cyclone in Basco, Batanes, bringing more than two months' worth of September rainfall and surpassing the previous record set by Typhoon Ruth in 1991. Meanwhile, Taiwan's Central Weather Administration issued maritime warnings for the Bashi Channel, leading to the evacuation of more than 11,000 people and the mobilization of nearly 40,000 soldiers for rescue efforts; at least 13 people were killed across the island, including nine from the Antai Tian-Sheng Memorial Hospital fire in Pingtung County. Overall, 18 people were killed, 731 were injured and one was missing by Krathon, leaving at least US in damages.
Meteorological history
The origins of Typhoon Krathon can be traced back to September 26, when the Japan Meteorological Agency (JMA) reported a tropical depression south-southwest of Kadena Air Base, Japan, characterised by a partially exposed low-level circulation centre with persistent deep convection in the southern semicircle and formative banding to the north. The United States Joint Typhoon Warning Center (JTWC) issued a tropical cyclone formation alert on September 27, noting that convective banding was wrapping into the centre and that the environmental analysis indicated a favourable environment for development due to low vertical wind shear, good equatorward outflow aloft, and warm sea surface temperatures of . On that same day, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) announced that the system had developed into a tropical depression named Julian, as it formed within the Philippine Area of Responsibility; Alt URL the depression was moving slowly south-southwestward due to weak steering flow.At 09:00 UTC, the JTWC upgraded the tropical depression, designating the system as 20W, noting an obscured low-level circulation centre that was assumed to be in the centre of rotating bands of convection organising into vortical hot towers. Satellite imagery indicated that the storm was steadily consolidating, with spiral bands of deep convection extending across three quadrants of the system and encircling the low-level circulation centre. On September 28, the depression intensified into a tropical storm named Krathon by the JMA, fueled by low vertical wind shear, warm sea surface temperatures, and high ocean heat content, while moving southwestward along the southeastern periphery of a mid-level subtropical high; however, Krathon slowed down over the last six hours and was located within a col region between two deep-layer subtropical highs, with satellite imagery indicating an improving appearance due to the development of a central dense overcast feature over the circulation centre. At around 18:00 UTC, the JMA upgraded the system to a severe tropical storm, utilizing the Dvorak technique to assess its intensity based on satellite imagery. Alt URL Krathon displayed strong equatorward outflow alongside a weaker polar channel, while the observed cirrus cloud suggested that a more radial outflow was beginning to develop as the system intensified. Alt URL Early the next day, both the JMA and the JTWC upgraded it to a minimal typhoon after it had opened a broad, raggedly-defined eye, Alt URL which had since become cloud-filled, and the system was moving north-northwestward between two mid-level subtropical highs. On September 30, Krathon's eye, measuring in diameter, was visible on infrared satellite imagery, Alt URL surrounded by warm temperatures of , Alt URL as the storm gradually moved west-northwestward and passed near Sabtang, Batanes. The typhoon displayed a distinct circular shape in the cloud tops across the eyewall region, with a contracting eye that was obscured in the center. At 18:00 UTC, the JTWC reported that the system had peaked as a Category 4-equivalent super typhoon after Krathon attained 1-minute sustained winds of . Early on October 1, the JMA upgraded Krathon to a violent typhoon, estimating its peak intensity with a minimum central pressure of and 10-minute maximum sustained winds of .
As it moved into the northern area of the South China Sea, the cloud top temperatures of Krathon sharply decreased over the past six hours amid warm conditions. An eyewall replacement cycle became apparent in radar imagery, with the secondary eyewall almost completely encircling the inner eye. Once the eyewall replacement cycle was complete, Krathon began warming cloud tops and displayed a weakened cloud-filled eye feature that caused upwelling and a decrease in ocean heat content, and it was moving southwest of Taiwan, located between a subtropical ridge to the east and another ridge over southern China and northern Vietnam. The following day, satellite imagery revealed that the system remained symmetrical; however, warming cloud tops became exposed due to increasing vertical wind shear. On October 3 at 12:40 p.m. local time, Krathon made landfall near Siaogang District in Kaohsiung, Taiwan, with its spiral bands of deep convection gradually weakening as it moved north-northeastward into central Taiwan, near the western edge of the Central Mountain Range. This made Krathon the first storm to make landfall on Taiwan's densely populated western plains since Typhoon Thelma in 1977. After making landfall, the system rapidly slowed down and deteriorated, exhibiting minimal convective activity and ultimately weakening to a minimal tropical storm. The JTWC discontinued warnings on the system as it moved inland, where the rugged southeastern mountain ranges of Taiwan eroded much of the deep convection associated with the circulation center as it weakened to a tropical depression. The Central Weather Administration noted that Krathon was the first storm to hit Kaohsiung in October, and the first since Tropical Storm Trami in 2001 to weaken into a tropical depression over Taiwan. The JMA continued to monitor the system as it emerged into the South China Sea, where it remained nearly stationary between two mid-level subtropical highs before dissipating on the same day.
Preparations Philippines Highest Tropical Cyclone Wind Signal
Shortly after PAGASA upgraded the storm, Tropical Cyclone Wind Signal No. 1 was issued for Batanes, Cagayan, Isabela, Apayao, Abra, Kalinga, the eastern and central portions of Mountain Province, the eastern portion of Ifugao, Ilocos Norte, the northern portion of Ilocos Sur, the northern portion of Aurora, Alt URL northern and eastern Nueva Ecija, Pangasinan, La Union, Quirino, Benguet, and the Polillo Islands. As Krathon intensified into a severe tropical storm, Signal No. 2 was raised for the northeastern portion of Cagayan and the eastern portion of the Babuyan Islands. As the storm continued to intensify, PAGASA raised Signal No. 3 for the northeastern portion of the Babuyan Islands On September 29, various local government units announced the suspension of classes on September 30 because of inclement weather caused by the storm, while PAGASA raised Signal No. 4 in Batanes, Babuyan Island, and Calayan Island.
The Commission on Elections ordered an extension of voters' registration for the 2025 Philippine general election, which was due to end on September 30, in areas affected by the storm. Around 1,110 people were evacuated across Cagayan Valley. A red alert warning was declared in the municipalities of Calayan and Santa Ana in Cagayan. The Ambuklao, Binga and Magat Dams opened their gates in anticipation of an increase in water levels due to the storm. According to the NDRRMC, ten people were preemptively evacuated.
Taiwan
The Central Emergency Operation Center advised against traveling to coastal and mountainous areas, while several schools, beaches, national parks and ferry services were closed across the island. All 25 water retention basins in Kaohsiung were emptied in anticipation of the storm. Warnings on shipping were raised by the Central Weather Administration in the Bashi Channel and the Taiwan Strait, followed by a land warning for Typhoon Krathon as the storm approached Taiwan. All schools and government offices in the island were ordered closed on October 2 and 3, while all domestic and at least 250 international flights were cancelled. Around 11,362 people were evacuated, while nearly 40,000 soldiers were mobilized for rescue efforts. Kaohsiung officials urged residents to be vigilant regarding the storm, recalling the devastation caused by Typhoon Thelma in 1977, which severely impacted the city.
Impact and aftermath
Philippines