Typhoon Yutu, known in the Philippines as Super 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 fortieth tropical depression, twenty-sixth named storm, twelfth typhoon, and the seventh super typhoon of the 2018 Pacific typhoon season, Yutu originated from a low-pressure area that formed in the western Pacific Ocean on October 15. The disturbance organized into a tropical depression on the same day, as ocean sea-surface heat content increased. Shortly after becoming a tropical depression, the Joint Typhoon Warning Center (JTWC) assigned the system the identifier 31W. The system continued to strengthen, becoming a tropical storm several hours later, with the Japan Meteorological Agency (JMA) naming the system Yutu. Increasingly favorable conditions allowed Yutu to explosively intensify, as the system maintained deep convection and subsequently became a severe tropical storm and then a typhoon.