The ornamental designs for a windowrainguard and wind deflector, as shown and described.
FIG. 1 is a front view of a window rain guard and wind deflector showing my new design;
FIG. 2 is a right side view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a top view the bottom is a mirror image thereof; and,
FIG. 6 is a perspective view thereof showing a window structure in broken lines for illustrative purposes only and forms no part of the claimed design.