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Cyclone Remal will probably cross the coast between Sagar Island of West Bengal and Khepupara of Bangladesh around midnight tonight (May 26), according to the India Meteorological Department (IMD)
The cyclone is likely to bring very heavy rain in South and North 24 Parganas, Purba Medinipur, Kolkata, Howrah and Hooghly districts of West Bengal on May 26 and May 27, the IMD said. It may also impact north Odisha on May 26 and 27. Extremely heavy precipitation may hit parts of northeast India on May 27-28. Heavy rain is likely in the districts of Paschim Medinipur, Purba Bardhaman, and Nadia in West Bengal on May 26 and 27, according to the weather agency.
Cyclone Remal, which is expected to generate wind speeds at 110-120 kmph, and gusts at 135 kmph, is a tropical cyclone. The National Disaster Management Authority (NDMA) classifies cyclones broadly into two categories: extratropical cyclones and tropical cyclones.
Here is a look at what a cyclone is and its types.
A cyclone is a large-scale system of air that rotates around the centre of a low-pressure area. It is usually accompanied by violent storms and bad weather. A cyclone is characterised by inward spiralling winds that rotate anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere, according to the NDMA.
Also known as mid-latitude cyclones, extratropical cyclones are those which occur outside of the tropic. They have “cold air at their core, and derive their energy from the release of potential energy when cold and warm air masses interact”, according to the US National Oceanic and Atmospheric Administration (NOAA). It added that such cyclones always have one or more fronts — a weather system that is the boundary between two different types of air masses. One is represented by warm air and the other by cold air — connected to them, and can occur over land or ocean.
Tropical cyclones are those which develop in the regions between the Tropics of Capricorn and Cancer. They are the most devastating storms on Earth. Such cyclones develop when “thunderstorm activity starts building close to the centre of circulation, and the strongest winds and rain are no longer in a band far from the centre,” NOAA noted. The core of the storm turns warm, and the cyclone gets most of its energy from the “latent heat” released when water vapour that has evaporated from warm ocean waters condenses into liquid water, the agency added. Moreover, warm fronts or cold fronts aren’t associated with tropical cyclones.
Tropical cyclones have different names depending on their location and strength. For instance, they are known as hurricanes in the Caribbean Sea, the Gulf of Mexico, the North Atlantic Ocean and the eastern and central North Pacific Ocean. In the western North Pacific, they are called typhoons.
