super-cold thunderstorm

It is common enough in summer to see a cumulonimbus cloud with a top flattened like an anvil. This is because the cloud has reached the ceiling of the troposphere where it is usually held, but some energetic storms can punch through the troposphere ceiling and enter the stratosphere where the cloud cools to below freezing.  The coldest temperature ever recorded occurred in March this year. There has been an increased number of such thunderstorms, a fact which is put down to climate change. The storms associated with super-cold thunderstorms are extremely powerful and can have a devastating effect.