1) Simple phobia 
Astraphobia, also known as astrapophobia, brontophobia, keraunophobia, or tonitrophobia, is an abnormal fear of thunder and lightning, a type of specific phobia. It is a treatable phobia that both humans and animals can develop. The term astraphobia derives from the Greek words ἀστραπή (astrape; lightning) and φόβος (phobos; fear). ==...
fear of thunder and lightning
fear of being struck by lightning
(as″trә-fo´be-ә) irrational fear of thunder and lightning.
Astraphobia: An abnormal and persistent fear of thunderstorms. Sufferers experience anxiety even when they realize the risk of harm is very small. Consequently, when indoors they might seek shelter under a bed, in a closet or in a basement. They generally keep a watchful eye on the sky and remain alert for reports of electrical storms. 'Astraphobia...
Astraphobia (or astrophobia) is the fear of thunder and lightning.
[n] - a morbid fear of thunder and lightning
astraphobia, astrapophobia 1. A morbid fear of lightning or of thunder and lightning. 2. An intensive fear of being struck by lightning or of thunderstorms.
noun a morbid fear of thunder and lightning
an abnormal fear of thunder and lightning.