mildness

(noun) good weather with comfortable temperatures. Synonyms: clemency.

(noun) acting in a manner that is gentle and mild and even-tempered. Synonyms: gentleness, softness. Examples: "His fingers have learned gentleness." "Suddenly her gigantic power melted into softness for the baby." "Even in the pulpit there are moments when mildness of manner is not enough."

(noun) mercifulness as a consequence of being lenient or tolerant. Synonyms: lenience, leniency, lenity.