Fairday's Riddle: Visible Force In Motion~

Hello, Riddlers! Can you guess our theme? I love the activity of watching these. Tune in Monday to find out how the answer ties into the story. See you all around the book block! ~ F

Curved and constant with peaks and dips; ravishing froth, silky slips. Back forth in ebbing ways; cast in motion for displays. Up, down, here and there ,  flowing almost everywhere. Forceful, smooth, swirling, high— describing styles in the eye.  

What am I referring to? Stop by this weekend for the answer

I gave you a clue!

FEAR NOT THE UNEXPECTED