Not exactly trad orthodoxy, but the sultry 60's chanteuse Julie London (big hit: Cry Me a River, which is actually quite beautiful, accompanied only by Barney Kessel on guitar) recorded an album called "Calendar Girl", which I believe has one song for each month of the year. Good quality copies of the LP are quite expensive, but a reasonable one might be dug up for a fair price. Then there's Paul Simon's song "April, Come She Will", which I think was actually a traditional song, and which mentions several months. And of course, "Shine on, shine on harvest moon, up in the sky, I ain't had no lovin' since January, February, June or July..."

Good luck, Chet W.