What causes thunderstorms?

Answer 1

Thunderstorms form when an air mass becomes so unstable that it overturns (convects) violently. "Unstable" means that the air in the lowest layers is unusually warm and humid, or that the upper layers are unusually cool, or oftentimes, both. Rising near-surface air in an unstable air mass expands and cools, and finds itself still warmer than it's environment, which causes it to rise even farther. If enough water vapor is present, some of this vapor condenses into a cloud, releasing heat, which makes the air parcel even warmer, forcing it to rise yet again. In thunderstorms, this process continues to feed on water vapor in the lower atmosphere, pumping air warmed by condensation as high as 40,000 to 60,000 feet (8 to 12 miles). Thunderstorms are more common in the afternoon over land, when daytime heating of the land by the sun causes the lower part of the troposphere to become unstable. Or, some thunderstorms can form from the upper atmosphere becoming unusually cool, due to the approach of an upper air disturbance. In this case storms can form at any time of day, even when there hasn't been daytime heating of the land. One absolute requirement, however, is there has to be sufficient water vapor to feed the storm. This is the fuel for the thunderstorm. As the storm uses up this fuel, it is converted to rainfall. Eventually, the storm stabilizes the atmosphere, through using up the excess water vapor, cooling the lower troposphere, and warming the upper troposphere.

Answer 2

Life cycle
A given cell of a thunderstorm goes through three stages: the cumulus stage, the mature stage, and the dissipation stage.

In the cumulus stage of a thunderstorm cell, masses of moisture are pushed upwards. The trigger for this can be solar insolation heating the ground producing thermals, areas where two winds converge forcing air upwards, or where winds blow over areas of high ground. The moisture rapidly cools into liquid drops of water, which appears as cumulus clouds. As the water vapour condenses into liquid, latent heat is released which warms the air, causing it to become less dense than the surrounding dry air, and so the air will tend to rise in an updraft due to the process of convection (hence the term convective precipitation). This creates a low-pressure zone beneath the forming thunderstorm. In a typical thunderstorm, some 5×108 kg of water vapour are lifted and the amount of energy released when this condenses is about equal to the energy used by a city (US-2002) of 100,000 during a month.

In the mature stage, the warmed air continues to rise until it reaches existing air which is itself warmer, and the air can rise no further. Often this 'cap' is the tropopause. The air is instead forced to spread out, giving the storm a characteristic anvil shape. The resulting cloud is called cumulonimbus incus. The water droplets coalesce into heavy droplets and freeze to become ice particles. As these fall they melt, to become rain. If the updraft is strong enough, the droplets are held aloft long enough to be so large that they do not melt completely as they fall and fall as hail. While updrafts are still present, the falling rain creates downdrafts as well. The presence of both updrafts and downdrafts during this stage can cause considerable internal turbulence in the storm system, which sometimes manifests as strong winds, severe lightning, and even tornadoes. If there is little wind shear, the storm will rapidly 'rain itself out', but if there is sufficient change in wind speed and/or direction the downdraft will be separated from the updraft, and the storm may become a supercell.

Finally, in the dissipation stage, updraft conditions no longer exist, and the storm is characterized largely by weak downdrafts. Because most of the moisture has precipitated out, there is not sufficient moisture in the lower air to sustain the cycle and the thunderstorm dissipates.

You could get more information from the link below...

Answer 3

hi there;
Warm moist air rises and smacks into the cooler dry air of the upper atmosphere. The cool air condenses into clouds which gets too heavy. The water then falls back to the surface as rain.
Thunder is the sound barrier being broken as a sudden electrical release occurs (lightening). The lightening release causes the air around it to superheat and expand at a rapid rate causing a shock wave. (The sound of the shock wave is the sound barrier being broken for a split second).
Lightening is caused by an electrical release from ground to cloud. Clouds are both positively charged and negatively charged. The upper part of the cloud is positive and the bottom is negative. Because the lower part of the cloud is negatively charged and the surface of the ground is positively charge the positive will release to the negative with an electrical path while releasing energy in the form of heat. That is what happens when there is a lightening strike at ground level. Often lightening will release the energy within the cloud itself without a ground strike.
I know this is over simplification of the process, but there you have it in a nut shell. :)

Answer 4

Hope this helps: http://en.wikipedia.org/wiki/Thunderstorms

Answer 5

When Hera says "I'm having a headache, dear" to Zeus.

Answer 6

Jesus listerning to thrash metal music and banging pan lids with wooden spoons

Answer 7

when clouds get full of rain (overly full usually)