Here's why:

* Troposphere: This is the lowest layer of Earth's atmosphere, where we live. It's where weather happens, as it contains most of the atmosphere's moisture and is where air movement (wind) occurs. Thunderstorms form within this layer.

* Stratosphere: This layer is above the troposphere and contains the ozone layer. It's generally too stable and dry for significant weather events.

* Mesosphere: This layer is above the stratosphere and is where most meteors burn up. It's too thin and cold for significant weather.

* Thermosphere: This is the outermost layer of the atmosphere. While it experiences extreme temperatures, it's also incredibly thin, so weather is not possible.

Let me know if you have any other questions!