Weather Phenomena by Ali Hussain

Geography project Lightning Tornadoes Hurricanes By Ali Hussain Weather Phenomena's

Tornadoes system development Although tornadoes occur in many parts of the world, these destructive forces of nature are found most frequently in the United States east of the Rocky Mountains during the spring and summer months. In an average year, 800 tornadoes are reported nationwide, resulting in 80 deaths and over 1,500 injuries. A tornado is defined as a violently rotating column of air extending from a thunderstorm to the ground. The most violent tornadoes are capable of tremendous destruction with wind speeds of 250 mph or more. Damage paths can be in excess of one mile wide and 50 miles long. Once a tornado in Broken Bow, Oklahoma, carried a motel sign 30 miles and dropped it in Arkansas! A tornado is defined as a violent rotating column of air. They can be categorized as “weak”, “violent” and “strong”. "; with weak tornadoes often having a thin, rope-like appearance, as exhibited by this tornado near Dawn, Texas. About 7 in 10 tornadoes are weak, with rotating wind speeds no greater than about 110 MPH. (looking west from about 1 mile.) Note the thin tornado like it says above.

Lightning system development Lightning is one of the most beautiful aspects of nature but it is a deadly phenomena known to man. With hot bolts hotter than the surface temperature of the sun and shockwaves beaming out in all directions. Lightning is a lesson in physical science and humility. Beyond its powerful beauty, lightning presents science with one of its greatest local mysteries. How does it work? The best place to be in during a lightning storm is the car as it will affect the car and not you. This statement is true. Lightning strikes somewhere on the surface of the earth about 100 times every second.

Hurricanes system development A hurricane is a severe tropical storm that forms in the North Atlantic Ocean, the Northeast Pacific Ocean east of the dateline, or the South Pacific Ocean east of 160E. Hurricanes need warm tropical oceans, moisture and light winds above them. If the right conditions last long enough, a hurricane can produce violent winds, incredible waves, torrential rains and floods. In other regions of the world, these types of storms have different names. Typhoon — (the Northwest Pacific Ocean west of the dateline) Severe Tropical Cyclone — (the Southwest Pacific Ocean west of 160E or Southeast Indian Ocean east of 90E) Severe Cyclonic Storm — (the North Indian Ocean) Tropical Cyclone — (the Southwest Indian Ocean) The hurricane starts of in the sea where the warm tropical water is and travels at great speed going at 300mph which is recorded to be the fastest. This hurricane took place in El Nino. Once the hurricane reaches land it slows down because it is running out of fuel which is the warm tropical water. Once the hurricane reaches land heavy rain, strong winds and vicious waves damage buildings, trees and cars. The violent/strong waves are called a storm surge. A storm surge is very dangerous and that is why you MUST stay away from the ocean during a hurricane. The hurricane is the ultimate storm.

How are formed In time now t, the formation of tornadoes are not fully understood by scientists. They usually form in a giant rotating thunderstorm called a super cell. Super cells form when cold polar air meets warm tropical air. The result is a great instability caused by the rising warm air. A squall line, or narrow zone of cumulonimbus clouds forms, giving life to the tornadoes. Lightning flashes, and heavy rains and hail begin to fall. Soon after, the easiest recognizable part of the tornado, the funnel, seems to descend from the base of the cloud. In actuality, it does not, but rather the pressure within the cloud drops due to the increasing wind speeds. As the pressure drops, it causes moisture in the air to condense. This action continues down the spiral, giving the impression that the funnel is descending from the cloud base. In addition to the visible funnel, there is also a hissing sound, which turns into a loud roar when the tornado touches the earth.

How Is formed Before lightning is formed, the cumulonimbus cloud of thunderstorms must become electrically charged. In most rain clouds, the bottom of the cloud is negatively charged and the top is positively charged. It is not known how the cloud becomes charged, but scientists have formed numerous theories to try to explain this phenomenon. These theories have been divided into two main categories: those that require ice and those that do not. However, meteorologists are leaning toward the theory that requires ice because lightning is not often seen unless ice has formed in the upper layers of the rain cloud.

How a Hurricane is formed Hurricanes begin as tropical storms over the warm moist waters of the Atlantic and Pacific Oceans near the equator. (Near the Philippines and the China Sea, hurricanes are called typhoons.) As the moisture evaporates it rises until enormous amounts of heated moist air are twisted high in the atmosphere. The winds begin to circle counter clockwise north of the equator or clockwise south of the equator. The relatively peaceful centre of the hurricane is called the eye. Around this centre winds move at speeds between 74 and 200 miles per hour. As long as the hurricane remains over waters of 79F or warmer, it continues to pull moisture from the surface and grow in size and force. When a hurricane crosses land or cooler waters, it loses its source of power, and its wind gradually slow until they are no longer of hurricane force--less than 74 miles per hour.

Tornado impact The damage from tornadoes comes from the strong winds they contain. It is generally believed that tornadic wind speeds can be as high as 300 mph in the most violent tornadoes. Wind speeds that high can cause automobiles to become airborne, rip ordinary homes to shreds, and turn broken glass and other debris into lethal missiles. The biggest threat to living creatures (including humans) from tornadoes is from flying debris and from being tossed about in the wind. It used to be believed that the low pressure in a tornado contributed to the damage by making buildings "explode" but this is no longer believed to be true. Cars are flung around and destroyed.

Lightning effect In addition to direct strikes, lightning generates electrical surges that can damage electronic equipment some distance from the actual strike. Typical surge protectors will NOT protect equipment from a lightning strike. To the extent possible, unplug any appliances or electronic equipment from all conductors well before a thunderstorm threatens. This includes not only the electrical system, but also the reception system. If you plan to be away from your home when thunderstorms are possible, be sure to unplug unneeded equipment before you leave. Another safe place is in the car it might not seem true but it is.

Hurricane Disaster During a hurricane, homes, businesses, roads and bridges may be damaged or destroyed by high winds and/or high waves. Debris from the high winds can damage property. Roads and bridges can be washed away by flash flooding, or can be blocked by debris. In particularly large storms (such as Hurricane Andrew), the force of the wind alone can cause tremendous devastation. Trees and power lines topple and weak homes and buildings crumble. These losses are not just limited to the coastline -- often damage extends hundreds of miles inland.