"An atmospheric closed circulation rotating counter-clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere". (NHC, Glossary of NHC Terms, 2007)
B. Wayne Blanchard, Guide To Emergency Management and Related Terms, Definitions, Concepts, Acronyms, Organizations, Programs, Guidance, Executive Orders & Legislation, A Tutorial on Emergency Management, Broadly Defined, Past and Present, B. Wayne Blanchard, USA 2007 (Last Modified 2008). http://training.fema.gov/EMIWeb/edu/docs/terms%20a nd%20definitions/Terms%20and%20Definitions.pdf, (Emr Mgt/ ND and Other Dzstr - Amer) {11}