inclemency vs rigourousness

inclemency and rigourousness both are nouns.

Word	Noun	Adjective	Verb	Adverb
inclemency	Yes	No	No	No
rigourousness	Yes	No	No	No

As nouns, inclemency and rigourousness are synonyms defined as:

Other synonyms of inclemency include hardness, harshness, rigor, rigorousness, rigour, severeness, severity, stiffness.

inclemency (noun)	rigourousness (noun)
excessive sternness	something hard to endure
weather unsuitable for outdoor activities	excessive sternness