There's a lovely, odd little song by Lemon Jelly called Nice Weather For Ducks, which references the idiom Lovely Weather for Ducks.
Despite conventional thinking, rain is not lovely weather for ducks, because the rain washes away the oil in their feathers that lets them float.
But accuracy aside, I could not find an origin for this phrase online, and now it has me curious.
Where does phrase originate, and how long has it been around?