The thunderstorms that do rotate, called supercells, are the ones that usually produce tornadoes. Thunderstorms also produce rain and sometimes hail, which frequently accompany tornadoes but is not caused by them.Thunderstorms usually occur as part of a larger storm system, but not always.A hurricane is a tropical cyclone with sustained winds of at least 74 mph (119 km/h).he thunderstorms that do rotate, called supercells, are the ones that usually produce tornadoes. Thunderstorms also produce rain and sometimes hail, which frequently accompany tornadoes but is not caused by them.
Integrated Access Device-IAD. A device that converts multiple types of input signals into a common communications format. IADs are commonly used in PBX systems to integrate different types of telephone devices (e.g. analog phone, digital phone and fax) onto a common digital medium (e.g. T1 or E1 line).
The Institute of Advanced Motorists (IAM) is a charity based in the United Kingdom and serving nine countries, whose objective is to improve car driving and motorcycle riding standards, and so enhance road safety, by using the British police's system of car and motorcycle control commonly known as the System.he Institute of Advanced Motorists Limited was incorporated on 10 March 1956 as a company limited by guarantee. A separate Institute of Advanced Motorcyclists  was registered in 2006, although it rarely or never features in IAM publications.