The 2024 Pacific typhoon season was a deadly and destructive season that became the deadliest since 2013. It was a below-average season in terms of accumulated cyclone energy (ACE), but was average in the number of named storms, and typhoons, ending a four-year streak of below-average seasons that began in 2020. The season was also the fifth-latest Pacific typhoon season and the first to start that late since 2020. Moreover, this season saw an unusually active November, with the month experiencing four simultaneously active typhoons since 2019 and featuring the most retired names in a single season—nine. Additionally, the Philippines also saw multiple consecutive typhoons making direct landfalls since 2006, with some at higher intensities.
Of the 26 named tropical storms, 13 became typhoons. The season ran throughout the year, though most tropical cyclones typically develop between May and November. The season's first named storm, Ewiniar, developed on May 25 and eventually intensified into the first typhoon of the season, while the last named storm, Pabuk, dissipated on December 25. Furthermore, Yagi became the season’s first super typhoon, as well being the strongest storm of this season on September 5 before it devastated Hainan and in Vietnam on September 7, becoming one of the strongest typhoons in 70 years to strike Vietnam according to the country’s government.
The scope of this article is limited to the Pacific Ocean to the north of the equator between 100°E and 180th meridian. Within the northwestern Pacific Ocean, there are two separate agencies that assign names to tropical cyclones which can often result in a cyclone having two names. The Japan Meteorological Agency (JMA) will name a tropical cyclone if it has 10-minute sustained wind speeds of at least 65 km/h (40 mph) anywhere in the basin. The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) assigns names to tropical cyclones which move into or form as a tropical depression in the Philippine Area of Responsibility (PAR), located between 135°E and 115°E and between 5°N and 25°N, regardless of whether or not a tropical cyclone has already been given a name by the JMA. Tropical depressions that are monitored by the United States' Joint Typhoon Warning Center (JTWC) are given a number with a "W" suffix; W meaning west, a reference to the western Pacific region.
Seasonal forecasts
During the year, several national meteorological services and scientific agencies forecast how many tropical cyclones, tropical storms, and typhoons will form during a season and/or how many tropical cyclones will affect a particular country. These agencies included the Tropical Storm Risk (TSR) Consortium of University College London, PAGASA, Vietnam's National Center for Hydro-Meteorological Forecasting and Taiwan's Central Weather Administration.
PAGASA released its first outlook on January 15 in their seasonal climate outlook predicting the first half of 2024. They predicted that zero to two tropical cyclones were expected to form, while two to four tropical cyclones are expected to form in April to June. PAGASA also noted that El Niño would persist between January and March; however, warmer than normal sea surface temperatures would gradually weaken.
Tropical Storm Risk (TSR) also released their first forecast on May 7, predicting below average activity with 25 named storms, 15 typhoons and 7 intense typhoons. This was primarily due to the dominant El Niño event at the time, which was expected to transition into a weak or moderate La Niña by mid-2024. TSR released their early July forecast on July 5, where they slightly decreased the amount of storms and typhoons, mentioning the same factors as their previous forecast. On August 7, TSR released their final forecast for the season, retaining the same number of storms. However, they further decreased the predicted ACE index, due to a slow start of the season and decreased tropical activity as of early August. Moreover, with the Pacific Decadal Oscillation being in a negative phase since the beginning of 2020, they also mentioned how this season could become the lowest five-year activity since 1965.
PAGASA released its second and final outlook on June 26, predicting 6-10 tropical cyclones to form between July to September, while 4-7 of those are expected to form between October to December. PAGASA also noted that El Niño conditions had also ended and a transition from neutral ENSO to La Niña is also likely between the former months.
Systems
Typhoon Ewiniar (Aghon)
On May 21, the Joint Typhoon Warning Center (JTWC) began tracking an area of atmospheric convection 441 km (274 mi) southeast of Palau, noting that the system was moving northwestward towards an environment favorable for tropical cyclogenesis. By May 23, the disturbance became a tropical depression. The depression would later enter PAR, assigning the name Aghon, a replacement name for Ambo. At 18:00 UTC, the JTWC designated the depression as 01W, based on surface observations from Guiuan. Aghon made landfall over Homonhon Island and subsequently Giporlos, Eastern Samar in the early morning of May 25 (PHT). It made five more landfalls over Basiao and Cagduyong Islands of Catbalogan; Batuan in Ticao Island; Masbate City; and Torrijos, Marinduque. At 12:00 UTC, 01W intensified into a tropical storm while it was still in Tayabas Bay, which prompted the JMA to name the storm as Ewiniar. In the morning of May 26 (PHT), the storm made its eighth landfall over Lucena, Quezon in Luzon island. Ewiniar later intensified into a typhoon over Lamon Bay The storm made its final landfall over Patnanungan in the Polillo Islands. The typhoon left the PAR on May 29 and continued to weaken due to subsidence around the mid-latitude. On May 30, Ewiniar transitioned into an extratropical cyclone south-southwest of Yokosuka, Japan. Then at 18:00 UTC on May 31, Ewiniar entered the baroclinic zone and an area of high wind shear.
Ewiniar resulted in ₱1.03 billion (US$20.88 million) in total damages in the Philippines, with ₱85.63 million (US$1.74 million) to agriculture and ₱942.55 million (US$19.14 million) to infrastructure, while also causing six deaths, injuring eight people, and impacting around 152,266 others. In Japan, heavy rainfall was observed in several regions, with a maximum of 52.5 mm (2.07 in) of rain being recorded in Miyake, Tokyo.
Tropical Storm Maliksi
On May 29, the JTWC began tracking an area of convection located 406 km (252 mi) southeast of Haikou, China. Being in an area of warm waters and low vertical shear and having southerly outflow, the system sustained a weak circulation, inhibited from development by another area of convection near Mainland China. It was recognized as a low-pressure area by the Japan Meteorological Agency (JMA) early the next day, before the agency upgraded it to a tropical depression at 06:00 UTC. Later that day, the JTWC issued a Tropical Cyclone Formation Alert (TCFA) on the depression since it had rapidly developed. At 00:00 UTC the next day, the JTWC upgraded the system into a tropical depression, designating it as 02W. Later, the JMA upgraded it into a tropical storm, and it was given the name Maliksi. However, the JTWC reported that it did not intensify into a tropical storm as it was disorganized, with the circulation elongating. At 21:00 UTC on May 31, the JTWC discontinued warnings on the system as it made landfall in Yangjiang, Guangdong. Soon after, the JMA last noted Maliksi as a depression on June 1 before weakening further into a low-pressure area the next day, as it tracked inland.
On May 30, the Hong Kong Observatory issued a No. 1 standby signal as the depression neared Hong Kong. The next day, it upgraded the warnings into a No. 3 Strong Wind signal. Although it was likely to not directly affect Taiwan, the Central Weather Administration noted that Maliksi's remnants were likely to merge with a frontal system and bring heavy rains to Taiwan over the weekend. In Macau, the storm caused unstable weather, with the Meteorological and Geophysical Bureau issuing Typhoon Signal No. 3. In China, torrential rainfall occurred, peaking at 272.3 mm (10.72 in) somewhere in the Leizhou Peninsula. Additionally, heavy rain was recorded in Fujian, Zhejiang and Jiangxi.
Tropical Depression 03W
On July 13, the JTWC began tracking an area of convection 423 mi (682 km) east-southeast of Da Nang, Vietnam. At the time, the disturbance was in a marginal environment for development, with high vertical wind shear offsetting good divergence aloft alongside warm sea surface temperatures. At 06:00 UTC of that day, the JMA designated the system as a tropical depression. The JTWC then issued a TCFA on the system the next day, noting its symmetrical center had improved as it moves northwest, though convection was disorganized. By 18:00 UTC the next day, the JTWC upgraded the system into a tropical depression, designating it 03W. However, they issued their last warning on the depression early the next day as it moved over Vietnam and rapidly weakened. Later that day, the JMA stopped tracking the depression as it dissipated.
Typhoon Gaemi (Carina)
On July 17, the JMA reported that a low-pressure area had formed east of Palau. Shortly after, both the JMA and the JTWC followed suit and upgraded the tropical depression, with the latter designating the system as 05W. The PAGASA followed suit a few hours later, recognizing the system as a tropical depression and naming it Carina. Early the next day, the depression intensified into a tropical storm, and was given the name Gaemi by the JMA. Due to a weak steering environment between the subtropical ridge to the northwest and east, the JTWC upgraded Gaemi to minimal typhoon around 21:00 UTC that day. On July 24, Gaemi later rapidly intensified and peaked at Category 4-equivalent intensity on the Saffir-Simpson scale at 21:00 UTC on 23 July, with 1-minute sustained winds of 230 km/h (145 mph) by the JTWC, 10-minute sustained winds of 165 km/h (105 mph) by the JMA, and a central pressure of 935 hPa (27.61 inHg). After stalling and executing a tight counter-clockwise loop near the coast, Gaemi slightly weakened into a below-equivalent typhoon status due to land interaction before it made landfall on the northeastern coast of Taiwan on July 24. Gaemi accelerated as it moved across the island and emerged into the Taiwan Strait just six hours after making landfall. Soon after, the JTWC ceased issuing advisories on the system as it made its final landfall at Xiuyu, Putian in Fujian Province. Once inland, the JMA downgraded Gaemi into a tropical depression on July 26 and continued tracking the system until it dissipated at 18:00 UTC of July 29.
The southwest monsoon, combined with Tropical Storm Prapiroon, brought heavy rains to southern and northern Luzon, triggering widespread flash floods that resulted in at least 126 deaths and caused damage estimated at US$2.31 billion across several countries.
Severe Tropical Storm Prapiroon (Butchoy)
On July 15, the JTWC started to monitor a persistent area of convection roughly 623 km (385 mi) southeast of Manila, Philippines. At that time, the disturbance was in a favorable environment for development, with warm 29–30 °C (84–86 °F), sea surface temperatures, low wind shear and good equatorial outflow. At 06:00 UTC the same day, the JMA designated the system as a low-pressure area. Shortly after, the JMA designated it as a tropical depression. The PAGASA declared the system a tropical depression a few hours later. Since the storm formed within the Philippine Area of Responsibility, the agency named it Butchoy. The JTWC began issuing advisories on the system, classifying it as 04W. It intensified into a tropical storm and was named Prapiroon by the JMA on July 21. The center of Prapiroon made landfall near Wanning, Hainan, with 1-minute sustained winds of 95 km/h (60 mph) on July 22. After making landfall, the storm maintained its well-defined eye while moving across central Hainan. Prapiroon soon encountered high wind shear and a dry environment, and by 06:30 ICT (21:30 UTC) on July 23, it made its second landfall in Quảng Ninh, Vietnam. After the system moved inland, both the JMA and the JTWC ceased monitoring it on July 24.
Typhoon Gaemi and Prapiroon, along with its precursor, significantly impacted the southwest monsoon over the Philippines, leading to heavy rainfall that caused 23 deaths, 9 people missing, and US$40.7 million in damages across several countries.
Severe Tropical Storm Maria
On August 5, the JMA stated that a tropical depression had formed. Later that day, the JTWC began tracking it, noting the depression was in an environment with low to moderate wind shear, warm sea surface temperatures, and good equatorward outflow aloft. At 09:00 UTC on August 6, the JTWC issued a TCFA on the disturbance, which was located 423 mi (682 km) north-northwest of Iwo Jima, along the eastern periphery of the monsoon gyre, prior to it being designated as 06W. The development of a central dense overcast and a ragged eye feature signified its intensification into a tropical storm, leading the JMA to name it Maria on August 7. Maria then turned northeastward, and intensified into a severe tropical storm on August 8 due to a favorable environment for development. Concurrently, the JTWC then reported that Maria had rapidly intensified into a minimal typhoon due to strong equatorward and poleward outflow. However, Maria's wind field became more asymmetric, with its associated convection shifting northward, causing Maria to weaken into a tropical storm on August 9. Around 00:00 UTC on August 12, the storm made landfall Ōfunato, a city in Iwate Prefecture, Japan with winds of 85 km/h (50 mph) before traversing northern Honshu and emerging into the Sea of Japan. The JMA continued to monitor the system until it was last noted at 18:00 UTC on August 14.
Record-breaking rainfall in Iwate Prefecture, with 19 inches (482.6 mm) in Kuji and 12.6 inches (320.0 mm) in Otsuchi—nearly double the average for August—led to controlled releases from the Taki Dam in Kuji, necessitating the evacuation of 8,300 people and the issuance of the highest evacuation alert level, though no damage or injuries were reported in association with Maria.