Eugene, OR
No. If there's already dirt, pollen, or dust on your glass, rain doesn't wash it away -- it clings to that debris and leaves streaks and mineral deposits behind as it dries. In a rainy climate like Eugene's, that cycle repeats all winter, which is part of why windows look dingy by spring.
Most of the year's rain here falls between November and February -- exactly the stretch when people assume the weather is doing the cleaning for them. In reality, that's often when windows pick up the most mineral buildup.
Professional cleaning removes the dirt and pollen layer first, so there's nothing left for rain to streak against afterward.
