Very nice blog, thanks for posting it. I bet you'll love the Norte. I walked in May several years ago and the weather was great. Only one day of non-stop rain that I can remember, though unfortunately it was on one of the more beautiful coastal walks between Pendueles and Llanes. Guess I'll just have to go back.
If by chance you find yourself with some time to kill in Colunga, consider a cheap cab ride (about 5 euros) to Lastres. It's another one of those touristy but beautiful towns perched on cliffs with narrow streets. Good restaurants and very nice views, and you won't have too many tourists in May. Buen camino, Laurie