The hottest town in Spain is Bailen, in Jaen, which averages 30.3 degrees in August and 30.2 in July. Bailen is a town rather than a city, and like many of the hottest places in Spain it is in the southern part of the country (Jaen is in Andalusia, in the south-east).

Of major cities, the hottest is Seville, which again is in Andalusia. It is cooler than Bailen, with an August average of 28.3, but still very hot. However, of the total hottest towns in Spain regardless of size, Sevile only stands at no. 20 - the south of Spain is known for its fierce, dry summer heat.
On the other hand, the northern regions can get very cold, especially the area around Girona, in Catalonia. In Valter in this region, the summer average temperature is only about 11 degrees, and in January it typically remains below zero. Galicia in the northwest is another very cold region.