My 89-year father has been using the expression "roomy moo" to describe bad weather. He says that it comes from a 16mm film that he saw after the war (World War II). The movie had something to do with a foreigner on an island who used the term to describe anything that went wrong, including bad weather.
Could thar be French? I'm terrinle at French, but Foogle translates rue mi mou as as soft midstreet. A pothole ort a puddle? Sortly someone here is able to speaj french?
I don't know about the moo, but rheumy was a common way of describing the type of wet foggy weather that would give you the sniffles.
I know French, but I don't think that's the right tree for this hunt. Like polistra, I'm inclined to think that rheumy would be right if it were restricted to discussing bad weather, and I also have no idea what the moo might be. Still, it is hard to see how rheumy would apply to other generic unpleasantness. This one is a puzzle.
Rue my mood ?