Apulia (Italy) is dominated by the Mediterranean macroclimate, more or less significantly modified by the influence of several geographic sectors and the complex surface morphology. This determines the occurrence of many regional climates with a corresponding wide range of vegetation types. However, it is possible to identify at least five homogeneous climatic areas, of different extent, in relation to the topography and the geographic context, and some sub-areas corresponding to characteristic phytocoenoses. The topographic limits of the different areas and sub-areas have been set based on the temperature values in the coldest months (January and February) of some known stations, interpolated by bicubic splines.