aosc200 - thunderstorms & lightning

thunderstorms

single cloud (cell) or cluster of clouds that produce lightning, thunder, rain & sometimes tornados/hail

A thunderstorm needs:

convection of warm moist air

where are thunderstorms most likely to form?

florida

single cell (cumulus stage)

needs a source of warm and moist air, water condenses & clouds spreads out in all directions, dry air from all directions promotes growths of droplets (aka rain)

single cell (mature stage)

lighting, rain, small hail, increase in updraft causes more droplet growth, precip. falls & evaporates (cools air) which causes downdraft and increases strength, downdraft lifts and mixes w/ updraft

single cell (decay stage)

updraft weakens & downdraft takes over, source of energy & moisture shuts down, storm weakens, clouds disappear and droplets evaporate, usually develops in mT air masses

multicell

wind keeps downdraft from clashing w updraft, strong downdraft aids updraft w also aids in formation of new cells

gust front

cold air (downdraft) hits the ground & spreads out, acts like a cold front and forces warmer air up which condsenses and forms a shelf cloud

squall line

line of intense individual storms, 6-12 hours, happens ahead of a front, strong wind shear tilts updraft & separates it from updraft

wind shear

significant change in wind speed and/or direction

mesoscale convective complex

multiple single cell storms in diff stages of development and indiv storms support other cells and they last forever if they have a sufficient supply of moisture

charge separation

occurs bc collision between ice crystals & droplets and graupel

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