sailors suit

[farm]

does anyone know the origins of the expression that a day will turn out fine if there is enoough blue sky to make a sailors suit. Is it true

[Marsh]

I know it with slightly different wording, for use when the whole sky is cloudy.  Once there is a patch of clear blue sky "big enough to make a sailor a pair of trousers", the weather will improve.  An earlier version, in Smyth's "Sailors' Word-book" of 1867, has "to make a pair of breeches for a Dutchman ".