Mark Hoover, CDC/NIOSH. Mark D. Hoover is a senior research scientist in the Division of Respiratory Disease Studies at the U.S. Centers for Disease Control and Prevention (CDC), National Institute for Occupational Safety and Health (NIOSH), in Morgantown, West Virginia.
This attracts the air from the valley, creating a breeze that blows from the valley floor up towards the top of the mountain. Often birds known as raptors, such as eagles, hawks, condors and vultures, float on these breezes to preserve their energy. This wind pattern is known as a valley breeze.
The opposite of this happens at night, usually, and is called a land breeze. In the summer, it is more likely that the wind will go from sea to land because of the aforementioned reasons. In the winter, the wind is more likely to be the opposite way (land breeze) during the day because the sea is warmer than the land.