free download PNG images :Hurricane,tornado

A tornado is a rapidly rotating column of air that contacts the earth's surface and cumulonimbus, or, in rare cases, the bottom of cumulus. They are often referred to as cyclones, cyclones, or cyclones, although the term cyclones is used in meteorology to name a weather system, with a low-pressure central area, a headwind around the northern hemisphere, and a clockwise direction in the south. Tornadoes come in many shapes and sizes, usually in the form of cumulonimbus funnels, which originate from the bottom of cumulonimbus clouds, under which there is a mass of rotating debris and dust. Most tornadoes have winds below 110 mph (180 km / h), span about 250 feet (80 m), and travel several miles (kilometers) before they dissipate. The most extreme tornadoes can reach winds of more than 300 miles (480 km / h) per hour, with a diameter of more than 2 miles (3 km), and stay on the ground for tens of miles (more than 100 km).

Tropical cyclone is a fast rotating storm system, which is characterized by low-pressure center, closed low-level atmospheric circulation, strong wind and spiral thunderstorm arrangement which produces heavy rain. According to its location and intensity, tropical cyclones have different names, including hurricanes, typhoons, tropical storms, cyclones, tropical depressions and simple cyclones. Hurricane is a kind of tropical cyclone, which occurs in the Atlantic Ocean and the northeast Pacific Ocean, typhoon occurs in the Northwest Pacific, and cyclone occurs in the South Pacific or Indian Ocean.