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.
Hurricane Katia (2011) Hurricane Katia was a classic Cape Verde hurricane that had substantial impact across Europe as a post-tropical cyclone. The eleventh named storm, second hurricane, and second major hurricane of the active 2011 Atlantic hurricane season, Katia originated as a tropical depression from a tropical wave over the eastern Atlantic on August 29. It intensified into a tropical storm the following day and further developed into a hurricane by September 1, although unfavorable atmospheric conditions hindered strengthening thereafter. As the storm began to recurve over the western Atlantic, a more hospitable regime allowed Katia to become a major hurricane by September 5 and peak as a Category 4 hurricane with winds of 140 mph (220 km/h) that afternoon. Internal core processes, increased wind shear, an impinging cold front, and increasingly cool ocean temperatures all prompted the cyclone to weaken almost immediately after peak, and Katia ultimately transitioned into an extratropical cyclone on September 10.