A severe tropical cyclone originating in the equatorial regions of the Atlantic Ocean or Caribbean Sea or eastern regions of the Pacific Ocean, traveling north, northwest, or northeast from its point of origin, and usually involving heavy rains.

Hurricane: A severe tropical cyclone originating in the equatorial regions of the Atlantic Ocean or Caribbean Sea or eastern regions of the Pacific Ocean, traveling north, northwest, or northeast from its point of origin, and usually involving heavy rains. It is also a wind with a speed greater than 74 miles (119 kilometers) per hour, according to the Beaufort scale.

As mentioned above it is a tropical cyclone which is a large-scale system of winds that spiral in toward a region of low atmospheric pressure. A cyclone's rotational direction is opposite to that of an anticyclone. In the Northern hemisphere, a cyclone rotates counterclockwise; in the Southern hemisphere, clockwise. Because low-pressure systems generally produce clouds and precipitation, cyclones are often simply referred to as storms. An extratropical cyclone is one that forms outside the tropics at middle or high latitudes. Extratropical cyclones usually have an organized front and migrate eastward with the prevailing westerly winds of those latitudes. A tropical cyclone forms over warm tropical waters and is generally smaller than an extratropical cyclone. Such a system is characterized by a warm, well-defined core and can range in intensity from a tropical depression to a hurricane. It is also called typhoon or hurricane which is an intense circular storm that originates over warm tropical oceans and is characterized by low atmospheric pressure, high winds, and heavy rain. Drawing energy from the sea surface and maintaining its strength as long as it remains over warm water, a tropical cyclone generates winds that exceed 119 km (74 miles) per hour. In extreme cases winds may exceed 240 km (150 miles) per hour, and gusts may surpass 320 km (200 miles) per hour. Accompanying these strong winds are torrential rains and a devastating phenomenon known as the storm surge, an elevation of the sea surface that can reach 6 metres (20 feet) above normal levels. Such a combination of high winds and water makes cyclones a serious hazard for coastal areas in tropical and subtropical areas of the world. Every year during the late summer months (July–September in the Northern Hemisphere and January–March in the Southern Hemisphere), cyclones strike regions as far apart as the Gulf Coast of North America, northwestern Australia, and eastern India and Bangladesh.

Compared to cyclone there is anticyclone which is a large-scale system of winds that spiral outward around a region of high atmospheric pressure. In the Northern Hemisphere the wind in an anticyclone moves clockwise, and in the Southern Hemisphere it moves counterclockwise.

Hurricanes are categorized according to the strength of their winds using the Saffir - Simpson Hurricane Scale. A Category 1 storm has the lowest wind speeds, while a Category 5 hurricane has the strongest. These are relative terms, because lower category storms can sometimes inflict greater damage than higher category storms, depending on where they strike and the particular hazards they bring. In fact, tropical storms can also produce significant damage and loss of life, mainly due to flooding.

Some time the factors like flow of water getting blocked as in Northern Russia. An unusually cold winter caused large amounts of ice to form along the river, which drains into the Barents Sea. When the river began to thaw, huge chunks of ice floated downstream, gathered at the mouth of the river, and formed a dam. The waters backed up for hundreds of kilometers and threatened to pour in on the 35,000 residents in the city of Naryen-Mar. In a last-minute attempt to save the town, the Russian air force brought in four SU-24 assault aircraft and dropped ninety-six 250-kg bombs on the ice, with little effect. Eventually the town had to be evacuated (Associated Press, June 4, 1998).