2019 Pacific typhoon season (Sassmaster/Layten)

The 2019 Pacific typhoon season was an annual event of tropical cyclone formation during which tropical cyclones known as "typhoons" form in the Western Pacific Basin. The activity continued nearly year-round due to an El Niño, a phenomenon in which favorable conditions are produced across the Pacific basin, leading to the formation of intense and potentially devastating storms, and most developed between May through October. The scope of this article is limited 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 should it be judged to have 10-minute sustained wind speeds of at least 65 km/h (40 mph) anywhere in the basin, whilst the Philippine Atmospheric, Geophysical and Astronomical Services Administration  (PAGASA)  assigns names to tropical cyclones which move into or form as a tropical depression in their area of responsibility located between 135°E and 115°E and between 5°N–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.