Simply because it's spring

Why is the sky so blue today?
Why is the robin's song so gay?
Why is the sun so warm and bright
Filling the earth with glorious light?
Why are the fields so green today?
Why do the clouds all float away?
Why does my heart with gladness sing?
Simply because it's spring!

Ok, so it's not spring yet, but there are tell-tale signs!

Playing outside!
Tulips!
Daffodils!
Crocuses!