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How do tropical cyclones form in the Southern Hemisphere?

The arrival of the summer season (November) brings the occurrence of Tropical Cyclones in the equatorial regions. These storms are characteristic of all tropical areas of the world. In the Southern Hemisphere, the cyclone season starts at the beginning of November and finishes the end of April. The season is the opposite in the Northern Hemisphere.

Tropical Cyclones are intense low-pressure systems, which in the Southern Hemisphere have well defined clockwise circulation, with mean (average) surface winds exceeding 63 knots. They derive their energy from warm tropical oceans and do not form unless the sea surface is above 26.5 Celsius. Depending on their strength; they are classified from category 1 to 5, category 5 being the most severe and destructive (with winds over 155 knots).

Cyclones often form between specific Latitudes, in the Southern Hemisphere this is usually 7'S and 15'S They are able to move quickly, are notoriously unpredictable and at times they even make loops or backtrack in direction.

Learn more in following Odyssey log:
December 4, 2001
'A Captain's Report - Weather Update'
"Besides the usual isolated thunderstorms, the arriving of the summer season (in the Southern Hemisphere) brings the occurrence of Tropical Cyclones. These storms are characteristic of all tropical areas of the world, and in the Southern Hemisphere, the cyclone season starts the beginning of November and finishes the end of April."
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