[10] On June 29, Taiwan's Central Weather Bureau (CWB) noted that sea surface temperatures had been gradually increasing and that there was a 50% chance of an El Nino event developing in the Pacific Ocean during the year.

[3] They also noted that systems tended to develop further away from Taiwan, had a longer lifespan and a greater intensity during El Nino events and urged citizens and local authorities to prepare.

[11] As the year opened, the Japan Meteorological Agency was monitoring a tropical depression that was located about 345 km (215 mi) to the northeast of Kuala Lumpur, Malaysia; however, the system was last noted later that day as it dissipated.

[12][13] On January 13, the JMA started monitoring a tropical depression that was located within an area of moderate to strong vertical windshear about 625 km (390 mi) to the east of Kuala Lumpur in Malaysia.

At the time, it had a developing low-level circulation center with deep convection, and was under an environment of low vertical wind shear and good divergence aloft.

[55] With strong vertical wind shear associated with a subtropical jet stream, along with rapidly cooling sea surface temperatures, the system continued to weaken.

[75] Turning northeastward as a mid-latitude trough weakened the subtropical ridge to the northeast, Mawar further intensified into a Category 2 typhoon early on the next day, as a ragged eye became visible on satellite imagery.

[81] Mawar further weakened into a category 1 typhoon as its low-level circulation center widened, and was entering a hostile environment due to its interaction with the jet stream.

[84] Late on the same day, the JTWC issued their final advisory on Mawar, as it was deeply embedded in the baroclinic zone and its low-level circulation center had decoupled behind its convection.

[87] Mawar brought torrential rain to parts of the Philippines including the Bicol Region while enhancing the southwest monsoon which triggered delays and cancelled of air flights.

[97][98] Early on June 14, the JMA upgraded Guchol to a severe tropical storm, and the PAGASA assigned the local name Butchoy on the system as it entered the Philippine Area of Responsibility.

The town of Nachikatsuura, some 400 kilometres southwest of Tokyo, ordered nearly 1,600 residents to evacuate, warning of the danger of landslides brought on by heavy rain, media reports said.

[146] Later on the same day, the JTWC upgraded Khanun to a tropical storm; also, the PAGASA named it Enteng as the system briefly passed the corner of the Philippine Area of Responsibility.

[168] On July 26, the JMA reported that a tropical depression had developed within an area of strong vertical windshear in the monsoon trough about 1,000 kilometres (620 mi) to the southeast of Manila in the Philippines.

[272][273][274] Steady weakening continued as Bolaven approached the Korean Peninsula and it eventually made landfall in North Korea late on August 28 before transitioning into an extratropical cyclone.

[327] On September 24, the JTWC upgraded the system to a tropical depression, although deep convection was displaced to the south due to moderate vertical wind shear associated with Jelawat, leaving its low-level circulation center exposed.

[328][329] The center then began to consolidate, with deep convection wrapping over its eastern quadrant, prompting both the JMA and the JTWC to upgrade the system to a tropical storm, with the former naming it as Ewiniar.

[330][331] Moving north-northeastward along the periphery of the subtropical ridge, Ewiniar's center continued to be displaced from the main convection due to moderate wind shear.

At the time, it had a broad but slowly developing low-level circulation center, and was under a marginal environment of warm sea surface temperatures, weak vertical wind shear and limited poleward outflow.

[352] Moving northwestward under the southwest periphery of the subtropical ridge, Maliksi continued to improve its center by the next day, with convective banding wrapping tightly towards it.

[369] By the next day, Gaemi entered the Philippine Area of Responsibility (PAR) as deep convection continued to wrap the system, with the PAGASA assigning its local name Marce.

A 59-year old fisherman was found dead along the shore of Nasugbu, Batangas, after two motorbancas with 3 fishermen onboard capsized amid big waves and strong winds caused by Gaemi.

[393] Early by the next day, Prapiroon intensified to a severe tropical storm, as it continued to improve, with tightly-curved banding over its center, while moving westward along the subtropical ridge.

[405][406] On October 15, the system reintensified to its secondary peak intensity, as deep convection wrapped its now-60 nmi (110 km) eye, while becoming quasi-stationary once again, entering a col area as nearby Severe Tropical Storm Maria tracked around the subtropical ridge.

[412][413] Prapiroon then returned to a northeastward track, cresting the western periphery of the subtropical ridge, while its center became fully exposed as cold air from the East China Sea advected into the system.

[431] This became short-lived, as its deep convection began to be sheared to the east of the system due to increasing westerly flow aloft associated with a subtropical jet stream.

[451] Early on November 12, the JTWC reported that a tropical disturbance had developed within an area of weak to moderate vertical windshear, about 315 km (195 mi) to the southeast of Manila in the Philippines.

[477][478] During December 26, Wukong continued to move through the Philippine islands, before the JTWC reported that the system had become a tropical depression, after its low level circulation center became fully exposed within an area of moderate to strong vertical windshear.

[487][488][489][490] On August 5, the Central Pacific Hurricane Center started to monitor a TUTT cell that had developed into a subtropical low, while located about 400 km (250 mi) to the southeast of Midway Atoll.

[496][497] During September 10, the JMA started to monitor a tropical depression, that had developed in an area of moderate vertical windshear between two upper tropospheric trough cells about 945 km (585 mi) to the southeast of Tokyo, Japan.