Imperceptibly they arrived

My swallows are back, 10 Oct 2013 - stealthily and imperceptibly they arrived; was I unconscious? 

Greater-striped Swallow sitting on my washing-line

They were very late this year, usually they arrive the beginning of September, maybe that's why I missed them. But we also had no rain in September, with our first shower happening on the 8th October. This leads me to believe they time their arrival with the rains... 

Wonder if they'll be using last year's half-completed nest? 

::