So this is how I packed for roughly 12 days in Spain, Portugal, Gibraltar, and Morocco. The temperature ranges from 35 (F, at might) to 65 (F, during the day).
I think I packed appropriately for the weather and the right amount (Note: Always check the weather before you go! My mom swore it was going to be cold/rainy, so she insisted we spend obscene amounts of money on gear from Patagonia. I checked the weather and found it would be just the opposite. Always check the weather, but be prepared, the nights get colder.)
One kinda funny thing I would recommend concerns underwear. I found that during backpacking or travel in general, bringing lacier or mesh type underwear (with cotton where its important!) is better since you can wash it and it’ll dry in 20 minutes.