The convention by which the motion of drops of water is represented by elongating them into a shape they never actually have in the real world appears in the picture of Peter jumping into the watering can. Yet interestingly, while this teardrop shape is like a backward arrow, we know the movement is away from the point only because we know the convention; Peter is himself a teardrop shape in this picture, but we assume he is entering the watering can, not leaving it—that he heads in the direction his body is pointed toward.
Perry Nodelman, Words About Pictures
LINES OF RAIN
White and blue lines
Black lines, and white for in front of the black
Ruler straight lines that extend across the entire canvas
RAIN IN THE DISTANCE
Storm Scents: It’s True, You Can Smell Oncoming Summer Rain, from Scientific American