Tonight is Beltane, May Eve, the spring fire festival: Nos Calan Mai in Welsh. In my garden yesterday the first apple blossom and the first six or seven cherry blossoms opened, and the first pea flower appeared. Tomorrow we may have snow again, but it will be quickly gone.
We have deferred our Beltane celebration to Saturday night, partly because of logistics, partly because the first local farmer's market of the season is Saturday morning, and we like to shop there for part of the feast. I feel there has been enough calendar reform over the centuries that any time within a few days of the date is good enough.
Last year I posted a description of an ancient Beltane celebration from my book Storyteller. On another blog this morning I read a beautiful description of a small modern celebration. There are many ways to celebrate the turning of the seasons. The main thing, I think, is to be aware.