Shoes, Sleeping bag ??

Last May it rained sixteen days in Porto. The high temperature was above 60F every day but one, and was generally around 65-70F and as high as 90F. The low was 50F.

Expect the same this year!

Well, last May was awful - I actually had to give up my pilgrimage due to bad weather and blisters requiring hospital treatment. However, that was not really 'normal' for Spain in May. April tends to be the wet month.
This year I am starting in late May [20th] hoping that maybe THIS time I'll miss the rainy season. I guess the answer to the question is - be prepared for rain, but also for really warm weather. The big question is - will this May in Spain be "normal"? And if you can answer that, please let us all know!!

Buen camino!

Stephen.
http://www.calig.co.uk/camino_de_santiago.htm

It rained 9 days in 2011 and 10 days in 2010 in Porto. Temperatures were similar to 2012.

If you travel without a sleeping bag you will be dependent on finding warm blankets somewhere at night. If you can guarantee that then you could risk not bringing a bag. I walked the Camino Frances in one July with only a fleece sleeping bag liner and woke up several times due to cold.

Waterproof clothing depends on whether you want to stay dry or not. Perhaps you don't mind wet feet. Some people hike in sandals. If you don't bring waterproof boots or shoes you might want to consider some waterproof socks such as sealskinz. With those you could walk in lightweight running shoes or sandals and still keep your feet dry.

Plan for everything: rain, mud, sun cold, hot and you'll be prepared.