Same joke, different setting:

The famous Viking explorer, Erik the Red, had a cousin named Rudolf the Red. Rudolf often sailed on voyages with Erik, serving as lookout.

On a voyage carrying settlers from Norway to Greenland, a mass of thunderclouds built up on the horizon and it looked like the longship was going to sail directly into them unless they changed course. Erik was about to instruct the helmsman to steer to the south when Rudolf pulled Erik aside and told him not to worry, that the rain would fall a bit to the north of their present course. So, the ship maintained course and, sure enough, the storm moved to the north, leaving them totally unscathed.

After the seeming narrow escape, a female settler approached Erik and asked how he knew the storm would narrowly miss them. "Well," replied Erik, "it was actually my cousin Rudolf who made the call. I always take his advice in such matters because Rudolf the Red knows rain, dear."