Beaufort scale used in Taiwan and mainland China, which are often affected by typhoons. Internationally, WMO Manual on Marine Meteorological Services (2012 edition) defined the Beaufort Scale only up to force 12 and there was no recommendation on the use of the extended scale. Wind speed on the 1946 Beaufort scale is based on the empirical relationship: Where "v" is the equivalent wind speed at 10 metres above the sea surface and "B" is Beaufort scale number. For example, "B" = 9.5 is related to 24.5 m/s which is equal to the lower limit of "10 Beaufort". Using this formula the highest
Tropical Storm Emilia (2006) storm briefly became disorganized, with the low-level circulation becoming ill-defined. Around the same time, Emilia passed about 175 mi (280 km) southwest of Manzanillo, which was its closest approach to southwestern Mexico; it is believed to have caused tropical storm force wind gusts along the coastline. Later that day, after turning west-northwestward, the convection increased markedly as an eyewall began to form. Operationally, it was estimated to have reached winds of 70 mph (115 km/h), and it was forecast to continue strengthening to attain Category 2 status on the Saffir-Simpson scale. However, the NHC later re-assessed Emilia as reaching peak