Bruna Vieira, Julia Vanina, Ryan Wasserberg! Supercell T-storms ...A supercell is an often dangerous convective storm with a very organized internal structure including a rotating updraft that allows it to keep going for up to several hours. Supercells are capable of producing severe weather including high winds, large hail, and strong tornadoes... Stages of Development! -Three basics are required for a thunderstorm to form: moisture, rising unstable air (air that keeps rising when given a nudge), and a lifting mechanism to provide the "nudge.“ -Thunderstorms have a life cycle of three stages: The developing stage, the mature stage, and the dissipating stage . -Thunderstorms form almost anywhere except the polar ice caps. They are especially dangerous in the Great Plains or Canadian Prairies. Stages of Development! Stage one. -The developing stage of a thunderstorm is marked by a cumulus cloud that is being pushed upward by a rising column of air. There is little to no rain during this stage but occasional lightning. The developing stage lasts about 10 minutes. Stages of Development! Stage two. The thunderstorm enters the mature stage when the updraft continues to feed the storm, but precipitation begins to fall out of the storm, and a downdraft begins (a column of air pushing downward). When the downdraft and rain-cooled air spreads out along the ground it forms a gust front, or a line of gusty winds. The mature stage is the most likely time for hail, heavy rain, frequent lightning, strong winds, and tornadoes. The storm occasionally has a black or dark green appearance. Stages of Development! Stage three. Eventually, a large amount of precipitation is produced and the updraft is overcome by the downdraft beginning the dissipating stage. At the ground, the gust front moves out a long distance from the storm and cuts off the warm moist air that was feeding the thunderstorm. Rainfall decreases in intensity, but lightning remains a danger. Cloud Formation! -Clouds are formed when air containing water vapor is cooled below a critical temperature called the dew point and the resulting moisture condenses into droplets on microscopic dust particles (condensation nuclei) in the atmosphere Weather Instrument! A thermometer is a device that measures temperature or temperature gradient using a variety of different principles. Safety Procedures! Outdoors: Stay low If possible, find shelter in a building Keep away from trees, tall objects, metal objects and water Discontinue use of phones and electrical Boaters and swimmer should get to land equipment. You may also want to unplug as a soon as possible If you're in a group caught outside, spread appliances and computers. out. If you begin to feel your hair stand on end, Avoid taking a shower or bath. If lightning strikes your house it may send this indicates lightning is about to strike. You should drop to your knees and bend a current of electricity across metal forward placing your hands on your knees plumbing throughout the house. and crouch down. Do not lie flat on the ground, this will only make you a larger target. Indoors: Stay off the phone Stay away from windows Use flashlights if the power goes out Historically Significant Weather! - May 5, 1995 in Fort Worth, Texas. “Many were caught in the open with little shelter when the supercell struck the fair with up to softball-size hail. Over 100 people were injured, with many of the injuries occurring as parents covered their children with their bodies to protect them from the plummeting chunks of ice.” Fun Facts! -Create a high threat to life and property. They can produce strong to violent tornadoes. -To calculate how far you are from a thunder bolt, count the seconds that have passed between a lightning bold and the next sound of thunder and divide the duration by five. The results are in miles. -Animals sit when there is a thunderstorm. -out of the 100,000 t-Storms tat occur each year in the U.S only about 10% are considered severe. Only a few reach supercell stage. The End!