What is the way to get rid of the fear and pessimism that afflicts a person when it rains and there are clouds, especially from lightning and thunder, and is there a specific supplication that can be said to remove this fear?

The believer's fear upon seeing the wind or hearing thunder is commendable, following the example of the Prophet, peace and blessings be upon him, whose face would show signs of displeasure when he saw clouds or wind, out of fear that it might contain punishment. The questioner should occupy himself with glorifying Allah upon hearing thunder, by saying: "Glory be to Him whom the thunder glorifies with His praise." However, if the fear is pathological, then it has a cure.