We had a spell of heavy pollen a couple of weeks ago up here, but it seems to have subsided when a couple of cold snaps came through. But I'm sure it will be back.
I've heard that pollen is both abrasive and caustic. Leaving it on a painted surface may damage the finish. And you have to be careful how you get it off. Simply brushing it off with a brush or microfiber cloth is a no-no. Static cling makes it hard to blow off, so about the only realistic thing you can do is break out the hose and rinse it off. Only to have a new coating of fresh pollen within 10 minutes. Which is BEFORE you can dry off the surface and put on a cover.
Yeah, I'm looking forward to getting a garage built....