Approximately 30Km from the coast of northern Spain and at a height of 244m above sea level the temperatures here are likely to be a degree or two below those on the coast.
Within 20Km south of Oviedo, the land rises to over 1500m and with 80Km to the south east, the Picos de Europa rise to over 2500m.
Temperatures will be cooler in these areas, particularly when the sun is not shining, and the rainfall will be higher. The weather will also be much more localised in the mountain areas.
Daily average temperatures for Oviedo
Source: World Climate