A tiny two-line weather saying linking blustery March to the flowers of May. Short enough to say in one breath and easy for a toddler to pick up.
From Mother Goose / Nursery Rhymes (traditional). See the whole collection.
March winds and April showers
Bring forth May flowers.
Public domain. Text from The Real Mother Goose (Blanche Fisher Wright, 1916), via Project Gutenberg. View the source edition