What is it?

First it starts softly
And you don't know it's happening

Then it gets bigger,
harder, faster,
not stopping

Then you see patches
of bright color on the ground

till it covers everything
in sight all around

It continues its pace
Sometimes harder
Sometimes not

Sometimes it look happy
Sometimes distraught

Now forceful
Now lazy

Now angry
Now hazy

Now it's just a wish..
Oh wait! It came back!

Now it's dancing
And it's hard to keep track

Oh, now it's beautiful!
Steady and slow

Building and packing
Continuing to grow

At night it turns blue
but it keeps on going

Gaining strength in the night
without you even knowing

It goes all night long
Yet in the morning
it's gone

All but the evidence
Piled up on the lawn.