How many hours did the storm which surpassed Typhoon Nora in 2015, grow from a tropical storm to a Category 5 hurricane?
Typhoon Nora (1973) Typhoon Nora was the fourth-most intense tropical cyclone on record. Originating from an area of low pressure over the western Pacific, Nora was first identified as a tropical depression on October 2, 1973. Tracking generally westward, the system gradually intensified, attaining typhoon status the following evening. After turning northwestward, the typhoon underwent a period of rapid intensification, during which its central pressure decreased by 77 mb (hPa; 2.27 inHg) in 24 hours. At the end of this phase, Nora peaked with winds of 295 km/h (185 mph) and a pressure of 877 mb (hPa; 25.91 inHg), making it the most-intense tropical cyclone on record (alongside Typhoon Ida in 1958) at the time; however, this pressure has since been surpassed by two other typhoons and one hurricane. The typhoon subsequently weakened and turned northwestward as it approached the Philippines. After brushing Luzon on October 7, the system passed south of Taiwan and ultimately made landfall in China on October 10. Once onshore, Nora quickly weakened and dissipated the following day.
Typhoon Francisco (2013) Typhoon Francisco, known in the Philippines as Typhoon Urduja, was a powerful typhoon that strengthened to the equivalent of a Category 5 on the Saffir-Simpson scale, according to the Joint Typhoon Warning Center. The 25th named storm and the 10th typhoon of the 2013 Pacific typhoon season, Francisco formed on October 16 east of Guam from a pre-existing area of convection. With favorable conditions, it quickly intensified into a tropical storm before passing south of Guam. After stalling to the southwest of the island, Francisco turned to the northwest into an environment of warm waters and low wind shear, becoming a typhoon. The JTWC upgraded it to super typhoon status on October 18, while the Japan Meteorological Agency (JMA) estimated peak 10‑minute sustained winds of 195 km/h (120 mph). Gradual weakening ensued, and after the typhoon turned to the northeast, Francisco deteriorated into a tropical storm on October 24. Passing southeast of Okinawa and mainland Japan, the storm accelerated and became extratropical on October 26, dissipating later that day.