the branch of meteorology that deals with the small-scale processes, physical conditions, and interactions of the lowest part of the atmosphere, esp. in the first few hundred feet above the earth's surface
See micrometeorology in American Heritage Dictionary 4
(mīˌkrō-mēˌtē-ə-rŏlˈə-jē)
noun
The study of weather conditions on a small scale, as in the area immediately around a building, smokestack, or mountain.