Vernal

(vər’-n^əl)

adj. 1. Relating to, or occuring in, spring

“In those vernal seasons of the year, when the air is calm and pleasant, it were an injury and sullenness against Nature not to go out, and see her riches, and partake in her rejoicing with heaven and earth.”
-John Milton

In Case You’re Spring-terested…

Like so much of our language, it comes from Latin, in this case the word vernalis, which is derived from ver (‘spring’).