convection as well as good outflow. The JTWC issued a Tropical Cyclone Formation Alert (TCFA) at 0100 UTC on November 19 due to a significant increase in organization. Five hours later, the Japan Meteorological Agency (JMA) started monitoring the system. Continuing to rapidly become better organized while moving west-northwest, the cyclone was classified as a tropical depression by the JTWC at midday. On the evening of November 19, both the JTWC and the JMA upgraded the system to Tropical Storm, prompting JTWC to name the system as Nina, shortly after developing banding features. Initially forecast by the JTWC to move slowly, instead, Nina accelerated while gradually intensifying. At 1600 UTC on November 20, Tropical Storm Nina passed south of Weno Island in the Chuuk Lagoon. Two hours later, the JMA upgraded Nina to a severe tropical storm. After moving away from the island on the morning of November 21, the JTWC upgraded Nina to a typhoon at 1200 UTC, with the JMA following suit early on November 22. Shortly thereafter, Nina made its closest approach to Ulithi, passing to the north. At 1600 UTC, Nina tracked about north of Yap. Typhoon Nina accelerated slightly as it traversed the open waters of the Philippine Sea. The storm continued to slowly deepen, though early on November 23, the system leveled off in intensity. That day, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) also monitored the storm and assigned it with the local name Sisang, upon entering the Philippine Area of Responsibility. However, midday on November 24, Nina entered a phase of explosive intensification , at a rate of an hour. Despite this, the JMA only increased the intensity slightly to . After developing a well-defined eye, the JTWC reported that Nina attained its peak intensity of , making it a low-end Category 5 system on the Saffir-Simpson Hurricane Wind Scale. At 1500 UTC on November 25, Nina moved ashore as it made landfall along the southern tip of Luzon at its peak intensity. Despite land interaction, little change in strength occurred until 0000 UTC on November 26, at that time, the system began to weaken. After traversing Luzon and Mindoro, the JTWC reduced the wind speed of the typhoon to . Although no eye was visible on satellite imagery, radar imagery indicated that an eye was present, but cloud-filed; henceforth, the JTWC increased the intensity of Nina to , equivalent