1 / 21

Thunderstorms & Tornadoes

Thunderstorms & Tornadoes. Question of the Day. Where would you expect to find the greatest proportion of Tstorms and why?. Cyclone. Circulation around ANY low-pressure center Intensity and size do not matter Tornadoes and Hurricanes are smaller than mid-latitude cyclones and more violent.

wilton
Download Presentation

Thunderstorms & Tornadoes

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Thunderstorms &Tornadoes

  2. Question of the Day • Where would you expect to find the greatest proportion of Tstorms and why?

  3. Cyclone • Circulation around ANY low-pressure center • Intensity and size do not matter • Tornadoes and Hurricanes are smaller than mid-latitude cyclones and more violent

  4. Thunderstorms • Storm that produces lightning and thunder • Characterized based upon the up/down draft of air NOT circular motion of air • Forms when warm, humid air rises in an unstable environment • Unequal heating of earth’s surface (Air-Mass Tstorms) • Unequal heating along with frontal wedging or oorgraphic lift (Severe Tstorms)

  5. Air-Mass Thunderstorms • Occur in mT air that moves Northward from Gulf. • Most frequent during Spring and Summer • Frequently around midafternoon • Thunderstorm Project produced a model of the life cycle of a Tstorm • Cumuls Stage • Mature Stage • Dissipating Stage

  6. Cumulus Stage • Formation of cumulus clouds allow for moisture to be at greater heights • Clouds grow vertically • Cumulonimbus clouds form • Dominated by updraft • Downdraft forms and failing precipitation causes drag • Entrainment intensifies downdraft

  7. Mature Stage • Officially starts when precipitation leaves the cloud • Updraft and downdraft exists side by side and grow the cloud • Anvil top forms when cloud reaches base of the stratosphere • Most active stage: Gusty winds, ligthning, hail/heavy precipitation

  8. Dissipating Stage • Dominated by the downdraft • Cooler air aloft and falling precipitation causes cloud to evaporate

  9. Severe Thunderstorms • Characterized by heavy downpours, flash flooding, strong/gusty winds, hail, lightning, and maybe tornadoes. • Must have winds over 58mph or hailstones .75 in diameter or produce a tornado

  10. SupercellTstorms • Single, powerful cell up to 65,000’ and 12-30 miles in diameter • 2000-3000/year in the US • Can form mesocyclones when updraft rotates

  11. Thunder & Lightning • Thunder is: Expanding air • Heat Lightning • Lightning is created due to separation of charges in a cumulonimbus cloud • Sheet Lightning • Within the cloud or between clouds • 80% of all lightning • Cloud to Ground Lightning • 20% of lightning strokes • Most damaging and dangerous • Flash is made up of individual strokes • Leader, step leader, return stroke, and dart leader

  12. Tornadoes • AKA: twisters, cyclones • Violent windstorms that are a vortex • Contains lower pressure inside the vortex than the surrounding areas

  13. Tornado Formation • Form in association with severe thunderstorms • Located wherever severe weather is: cold fronts, squall lines, hurricanes, supercells • Only tornado if funnel cloud touches surface

  14. F-Scale • Fujita Intensity Scale • Determined based upon damage produced

  15. Tornado Forecasting Watches Warnings • Alters public to POSSIBLITY of tornadoes over a specific area for a certain time period. • 65,000sq.km for 4-6 hours • Issued by local NWS • ACTUAL sighted tornado in an area or indicated by radar • Smaller areas and for shorter periods of time

More Related