Rain covers makes it possible to shoot in any weather. A simple rain cover protects your camera and lens from water, dust, and snow. It’s cheap insurance that lets you keep shooting when the weather turns bad. I read a tip somewhere to use rain caps that hotels provide. You just stick the lens out of the hole where your head normally goes.

Pentax is famous for its weather proofing and rugged camera houses, but especially in extreme rain it is just a question about time before moist gets into the camera house.