tempestuousness vs storminess

tempestuousness and storminess both are nouns.

Word	Noun	Adjective	Verb	Adverb
tempestuousness	Yes	No	No	No
storminess	Yes	No	No	No

As nouns, storminess is a hypernym of tempestuousness; that is, storminess is a word with a broader meaning than tempestuousness:

tempestuousness (noun)	storminess (noun)
a state of wild storminess	violent passion in speech or action
a state of agitation or turbulent change or development	the state of being stormy