@Barbara Racz We walked 17 April-17 May. It can be much colder at elevations. We hit snow in the Pyrenees and near Burgos. There were some days on the Meseta with a fleece and a shell jacket (gloves and toque) that the winds and cold produced almost hypothermic conditions.
You will need rain protection, if this 'breathes' it could double as a shell jacket. If not you will some sort of wind proof breathable jacket. The ski jacket may be too heavy?
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