Did you know that the cruising altitude of most passenger jets on long flights is about 35.000 feet? That is a long way up, more than 6.5 miles! That area of the atmosphere is called the lower Stratosphere. One of the main reasons why jets travel that high is because the atmosphere there is more stable. There is much less turbulence there because the Sun's heating of the atmosphere affects the lower portions more than the higher ones. Why is that? Because ocean's, lakes, rivers and even the ground absorb heat from the Sun and release it back into the air, and also gravity pulls down on air molecules making the lower atmosphere denser.
Cumulonimbus (thunderstorm) Cloud
So the lowest level of the atmosphere, called the Troposphere is warmer and has much more air movement than further up. So if you want smooth sailing, you have to head higher!
There are five levels of atmosphere surrounding the Earth. Starting from the ground they are, the Troposphere, the Stratosphere, the Mesosphere, the Thermosphere, and the Exosphere. The Exosphere and the Thermosphere are where we see the Aurora Borealis, and the Aurora Australis, the Northern and Southern lights, but have little or no atmosphere and so have nothing to do with weather.
Nothing much happens weatherwise in the Mesosphere either. If you were coming down from above, the Stratosphere is where things start to happen. The Stratosphere is where you'll find the Ozone layer, Somewhere around 9 to 18 miles above the Earth's surface. The Ozone layer protects us from the most harmful rays of the Sun. Without it, we couldn't survive.
During strong storms, Cumulonimbus clouds build up in the atmosphere. Sometimes they get so high they reach the Stratosphere. When this happens their tops start to flatten out. So if you have ever watched a thunderstorm start to take shape and see the giant Cumulonimbus clouds with flattened tops you are actually looking at the top of the Troposphere layer of the atmosphere! Pretty cool, right?