(WVNS) — We’re taking it back to the basics this time around and breaking down how a thunderstorm forms. We’ll get a bit technical with this one too, so let’s dive into it.
We’ll start by identifying the three basic pieces needed for a thunderstorm. Lift, Instability and Moisture. These will all come into play at different points during the process, but ultimately are all necessary pieces!
To start off we need an environment for our storm to form in. We’ll take this cube and label it as our atmosphere, and give it a uniform temperature throughout of 60-degrees to make this simple. At the bottom or the ‘surface’ of our atmosphere, we’ll add a layer of air that is 70-degrees. Now the fact that the air at the surface is warmer than the air above is important. The air below is now less dense and wants to rise, this makes the layer of air ‘unstable’. We’ll also assume this layer of air is saturated, which checks moisture off the list too.
Almost always though, a parcel of air needs a nudge to get it started. This is where lift comes into play. In this example, we’ll use a cold front as our source of lift as many are already familiar with it. When the cold front rushes by, cooler air is wedged underneath our warmer parcel of air forcing it upwards. From there the parcel continues to rise on its own since it is unstable.
As the parcel rises it begins to cool, and the water vapor in the layer of the air begins to condense. This is where the cloud of the storm begins to take shape. We’ll see it grow until it reaches the equilibrium level where the parcel and the air temperature are the same, this is where our parcel stops rising. Our cloud stops growing up here and now starts to spread outward creating the anvil shape of our cumulonimbus cloud.