A mud dauber wasp, of some sort, built her nest on my front step in the spring of 2015. The nest location was in full sun (southern exposure) and out in the open, so that it had no rain protection. In April of 2016, the wsp emerged, leaving the exit hole. So the larval wasp developed successfully, in a nest with full exposure to weather. Striking to me was that the mud nest did not melt away, despite the extensive rains we had.
This nest, therefore has been exposed to a full year of rain, and still looks, for the most part, like it did when it was first constructed.
Click to enlarge.