When this heat wave breaks, there are going to be some massive thunderstorms, right? Not necessarily. Although there is potential energy present in hot and humid air, these are just two of many elements that are required for severe thunderstorms.
When air is hot and humid, there is certainly more thermodynamic energy available once that air rises enough to cool and condense. However, there needs to be enough wind aloft and it helps if the wind aloft is blowing across the wind near the ground. This keeps the downdrafts of rain from snuffing out the air rising into the storm. Such wind shear also encourages rotation which can add to the wind velocity of the updraft and make the storm more dangerous.
Other upper atmospheric conditions, such as temperature and humidity, can have a lot to do with how strong storms can be. So the presence of hot and humid weather is not a signal to head for the basement when a storm moves in.
