Complex sentence: The coolest months tend to be from November to January, and the warmest from March to May.The topography affects the region's climate as well; the seasons come to each slope of the hills at slightly different times.
Split into simpler sentences: The coolest months tend to be from November to January, and the warmest from March to May. Of course, the topography affects the region's climate as well; making the seasons come to each slope of the hills at slightly different times.