"Oh, please come in!" I cried, for it had been so still in the house that I supposed my friend and hostess had
gone to see one of her neighbors. The first cold
northeasterly storm of the season was blowing hard
outside. Now and then there was a dash of great
raindrops and a “flick of wet lilac”leaves against the
window. but I could hear that the sea was already stirred.

What does a "flick of wet lilac leaves" imply, or connote, in the second paragraph?