I find that the shadow of Peewee’s shoes to have shifted to the right and left in panel #3, but in the first two panels those shadows are only to the left.
For Nancy’s shoe shadows, in the first two panels, the shadows are to the left and the right, while in panel, #3 Nancy’s shoe shadows are only on the left side of said shoes.
Three Rocks can only do so much. Sluggo is a geometric property of the strip. The cloudburst is a GAG.
I’m left wondering if Ernie overlooked the diagonal angles of the rain storm in panels #1 and #2, delivering Nancy’s appearances on a telephone.
If I imagine myself looking in from outside Sluggo’s broken window in panel #3, the rain direction has a different angular direction of the rain storm signifiers in panels #1 and #2.
Those rain drop diagonals are reversed and Ernie provides us viewers with no outside point-of-view of panel #3 where Sluggo’s voice appears.
I enjoy this kind of Bushmiller puzzle-treatment that Ernie often gives to his strips.
Talented comic strip artists take liberties with sound production in a strip.