I don't even pretend to claim that this is a decent translation, but this is a pretty direct translation:

It rains in my heart
Like it rains in the city.
What is the langeur
That penetrates my heart?

Oh soft sound of the rain
On the ground and on the rooves!
For a heart who saddens itself
Oh, the song of the rain!

It rains without reason.
In this heart that pierces
What! No treason?
This dirge is without reason.

It's by far the worst pain
To not know why,
Without love, without hate,
My heart feels so much pain.


That's as word for word as I could get, but it's not that poetic. Just reread the poem, now that you know the subject, ;-)