Seattle, WA
No. Rain only looks like it's cleaning your windows. If dirt or pollen is already on the glass, rainwater clings to it and leaves streaks and mineral deposits when it dries, rather than rinsing it away.
Seattle's spring pollen season followed by a return to rain is exactly the combination that produces streaking -- pollen lands, rain hits it, and it dries into a film rather than washing clean.
A proper cleaning removes the existing dirt and pollen layer, so there's nothing left behind for the next rain to streak against.