Good Afternoon Ian,
I hope you are having a good day so far.
In the winter months from mid November to the end of March it can be very cold, especially inland, and even in Andalucia. For Christmas tours to Spain you should take plenty of warm clothing.
As Spain is such a large country with such varying temperatures it is best to check weather forecasts yourself just prior to travel. Information is readily available on the internet.
Comfortable shoes are a must as there can be a lot of walking involved on some excursions.
Kind Regards,
Mildred