It was really nice a couple of days ago but now the garden is flooded again and it was so chilly I thought it might snow, "Ne'er cast a clout till May be out", as the English say.
Or in the French, "En avril, ne te découvre pas d'un fil; en mai, fais ce qui te plaît " or the Spanish, "Hasta el cuarenta de mayo no te quites el sayo".