Hurricane Andrew in is an example of this. And those powerful storms have the potential to produce a lot of rain, flooding, and strong storm surges. A supercell thunderstorm strikes in South Dakota. Among the most severe storms, supercells can bring strong winds, hail, and even tornadoes. See more extreme weather pictures. Scientists just call these storms different things depending on where they occur.
In the Atlantic and northern Pacific, the storms are called hurricanes, after the Caribbean god of evil, named Hurrican. In the northwestern Pacific, the same powerful storms are called typhoons. In the southeastern Indian Ocean and southwestern Pacific, they are called severe tropical cyclones. In the northern Indian Ocean, they're called severe cyclonic storms. In the southwestern Indian Ocean, they're just called tropical cyclones.
To be classified as a hurricane, typhoon, or cyclone, a storm must reach wind speeds of at least 74 miles an hour. While the Atlantic hurricane season runs from June 1 through November 30, the typhoon and cyclone seasons follow slightly different patterns.
In the northeastern Pacific, the official season runs from May 15 to November In the northwestern Pacific, typhoons are most common from late June through December. And the northern Indian Ocean sees cyclones from April to December. All rights reserved. Find out how they form, and what's being done to better predict their impact. Lightning Strikes A supercell thunderstorm strikes in South Dakota. Share Tweet Email. The "Saffir-Simpson" scale rates hurricane strength in this way from Category 1 to Category 5.
These categories were chosen based upon the amount of damage that each category can produce. EXTREME: outer walls damaged, roof failure on small buildings, extensive damage to doors and windows, mobile homes destroyed. In low-lying areas, much of the damage from hurricanes can be from the "storm surge", in which water being blown onshore by the high winds rises rapidly. The storm surge can destroy the lower floors of some buildings, or even destroy the foundations of residences causing the homes to wash away.
The storm surge can also trap residents from evacuating along low-lying escape routes. Hurricanes almost always travel poleward at the end of their life cycle, helping to transport excess heat out of the tropics toward higher latitudes. Sometimes the hurricane will merge with an extratropical non-tropical storm system, which can cause temporary intensification of the storm, as was the case with Hurricane Sandy which hit New England in late October, Hurricanes gradually die as they move over cooler waters, which do not have the heat energy necessary to evaporate sufficent water vapor into the atmosphere to fuel the hurricane.
If the hurricane crosses over to land, the heat source is removed entirely. With the removal of the energy source, and the greater surface friction of the land's terrain and vegetation, the hurricane's winds rapidly decrease. A hurricane adds fuel to its own fire by drawing surface air toward its low-pressure center. The tight pressure gradient nearer the center means that the winds grow stronger as the air approaches the eye.
The faster the wind blows, the more evaporation takes place this is why you blow-dry wet hair or hands instead of merely warming them. In short, evaporation and condensation of water are the keys to understanding the power of tropical cyclones. How strong is the engine that powers a tropical cyclone? Part of this energy is expended reducing the central pressure of the storm and strengthening the winds.
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