A microclimate is the weather of one small area when that area does not match the weather around it. A valley can stay colder than the hill next to it. The shady side of a building can stay wet after the street has dried. Gardeners love this word, because a wall, a tree, or a slope can change what will grow there. It is a real science word, but you also hear it in ordinary talk about cities, parks, and homes. It does not mean “a little climate change,” and it does not mean the weather for one hour. It means this small spot has its own usual weather pattern. Though actually, the “small” can still be as big as a neighbourhood or a whole hillside — it is small next to the region, not small like a teacup.