Well, actually no. Not always and not everywhere. If you've studied your geography, you'll know that temperatures drop as altitude rises. But do you also know that "...the average height of the ground (in Spain) is greater than in any European country except Switzerland..."? (The New Spaniards; John Hooper, Penguin 2006.)
So expect many parts of Spain to get very cold at this time of year. Here's a report from El País with a video for you to translate.
If you enjoyed this resource, you might enjoy reading about my life here in Spain as an immersion teacher of a class of primary children. Zen Kyu Maestro: An English Teacher´s Spanish Adventure is published as an eBook by Monday Books. There´s a free sample chapter available to download here: Zen Kyu Maestro