Daxzentu,
Any season can be a wonderful time to walk, but in late autumn/winter you MUST be prepared for varied weather. Nights can be extremely cold with freezing rain or snow. Learn to read the sky for possible storms, ask locals for advice and take every precaution.
Sillydoll who is a Forum member has compiled encyclopedic information on
Winter Walking. Other good accounts of winter walking by Forum member Kialoa3 are
his 2010 and later blogs
In bad weather many steep descents on the camino would be treacherous and following smaller parallel roads might be necessary. Winter 2012/13 the Napoleon route from SJPdP to Roncesvalles was filled with several meters of snow and in effect closed to pilgrims thus necessitating the use of the Valcarlos alternate; read more here about this
hazardous situation
Other difficult stretches after storms might be from Najera to Santo Domingo de la Calzada or across the Montes de Oca from Villafranca as well as Monte Irago and, of course, O Cebreiro.
Not all albergues will be open, but the welcome at those albergues which are is often most sincere. Most will usually be heated and/or have blankets. Generally the hospitaleros know who is open on the next stage.
When walking in late autumn/winter only in larger places such as Roncevalles, Logrono and Santo Domingo de la Calzada and, of course, Santiago have I ever seen a cluster of more than 20 pilgrims at one time. It is easy to walk alone and in smaller albergues you might be the only pilgrim.
Twice during winter caminos I have sat out true blizzards; in Villafranca Montes de Oca, February 25, 26, 2006 and Foncebadón, March 5,6, 2009. Even late November 2012 the climb up to O Cebreiro was packed with snow. You can see the snow and read my blog accounts of these three memorable storms
here. Luckily open albergues offered welcoming shelter, heat and companionship.
Most of us who walk in late autumn and winter wear and carry lightweight but warm layers which can easily be added or removed while walking. Each pilgrim develops a favorite combo. Scan the Forum's
Equipment topic to see a multitude of varied approaches.
Here's mine
Happy planning, stay safe and Buen Camino,
Margaret Meredith