Cumulonimbus and aviation at this altitude, updraughts with speeds that can exceed . Such an updraught speed corresponds to the wind speed of a small hurricane. The speed can even exceed . The maximum number in the Beaufort scale is 12 ("hurricane force" wind) and is assigned to wind speeds of 64 knots or greater. If the Beaufort scale were extended, these updraughts would have a Beaufort number of 14 "in the vertical direction". The turbulence is then "extreme" at this altitude. Moreover, the diameters of the updraught columns vary between 2 km (air mass thunderstorm) and 10 km (supercell thunderstorm). The height
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