Convective Available Potential Energy, in French : Energie potentielle de convection disponible. Behind this abstruse acronym hides a powerful tool for forecasting thunderstorms. The CAPE is measured in joules per kilogram of air (J / Kg) and defines the vertical thrust energy of a hot air particle in a colder atmosphere. In other words, vertical acceleration of the air particle will be directly related to this energy measurement.
The CAPE therefore gives a measure of the instability of an air mass. This is one of the parameters used by meteorologists to estimate the violent potential of a thunderstorm. Indeed, over the updraft is strong, more it can support large hails, or a large amount of precipitation.
To the least scientific of us, Olivier Bouyssou, as a great teacher, explains :
"The CAPE is not a sufficient condition for the appearance of thunderstorms. By analogy, it can be compared to the powder in the barrel, but you also need the wick... and the lighter to light it. Actually, is an interesting indication if it is associated with precipitation. Values in France > 1500 J / Kg + Rainfall is often associated with severe thunderstorms. It must therefore be interpreted as a probability. "
Weather4D adds this data by default in the parameters available when creating a zone. This is essential information for predicting the occurrence of storms. To activate, you must select it in the display options of each model.
The intense CAPE episode above shows the risks of stormy conditions that can occur early in the summer season in the Mediterranean, and which, with the increasing warming of the sea temperature, can cause the creation of Medicanes (¹)
The more knowledgeable of you can visit the articles on the CAPE in Wikipedia :
(¹) You said « Medicane » ?