At the peak of the cyclone season and after the passage of tropical storm Fiona, which is now called a hurricane, here is something to clarify the lexicon of these weather phenomena.
The storms are born from tropical depressions in the west of Africa and gain strength by crossing the Atlantic before hitting, in our case, the Caribbean islands. The hurricane season begins in June and ends in November. The peak in September is linked to the increase in ocean temperature, which must be high enough to cause significant evaporation. After its formation, the tropical depression turns clockwise in the southern hemisphere and counterclockwise in the northern hemisphere. Storms become cyclones, hurricanes, or typhoons depending on the geographical area where they are located.
In summary, the vortex phenomenon is identical, contrary to its nomenclature. In the southwest Indian Ocean and the southwest and the north Pacific Ocean, we speak of cyclones. In the northwestern Pacific, violent storms are called typhoons. And finally, in the North Atlantic and the Northeast and Southwest Pacific, a storm is called a hurricane, from “Hunraken”, the Mayan god of storms, which gave hu-ra-kan the name of the god of evil in the Caribbean.
This basin of formation of tropical cyclones is the most studied including the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico, and affects the United States, Mexico, the Caribbean, Canada, and Central America. If the terms depression and tropical storm are characterized by a sustained wind speed of less than 63km/h for the first and 64 to 117km/h for the second, different categories exist to classify a hurricane. Meteorologists use a scale of measurement to have benchmarks of intensity. The Saffir-Simpson scale was designed in 1969 by engineer Herbert Saffir and the director of the National Hurricane Center at the time, Robert Simpson.
It is divided into five categories: Category 1: from 118 to 153 km/h, category 2: from 154 to 177 km/h, category 3: from 178 to 209 km/h, category 4: from 210 to 249 km/h and category 5: over 249 km/h. Irma, which devastated St. Martin in 2017 and blew up to 287 km/h (estimated at 295km/h) with gusts to 360km/h, received the title of super-cyclone.
The World Meteorological Organization assigns a name to a tropical cyclone that exceeds a certain intensity, in the interest of public safety. The naming of this phenomenon dates back to the 18th century to differentiate each cyclonic episode. The Spaniards based their names, for example, on the calendar of the patron saint of the day.
At the beginning of the 20th century, the Australian meteorologist Clement Lindley Wragge was the first to give names to hurricanes, choosing the name of a woman or the name of a politician he did not like. Currently, for the North Atlantic, the Caribbean, and the Gulf of Mexico, the National Hurricane Center (based in Miami, Florida) has six lists of 21 names every six years, one list per year. These lists are in alphabetical order, skipping the letters that are too rare (such as Q or U) with alternating male and female names (in English, Spanish and French). After Fiona, it will be Gaston, which we hope is less devastating than its predecessor.