Notes on Local Winds
1. Local Wind is a wind that extends for a distance of 100 km or less.
2. Local winds are caused by a difference in air temperature – just like large-scale winds,
3. Examples are:
A. Land Breeze: Cooler air descends over the land and warmer air rises over the
water. This happens at night. Therefore the cooler land breeze
blows out to sea. So the wind blows from the land out to the
sea.
B. Sea Breeze: The air rises over the land and flows out to the sea; and as it
cools it sinks. This usually begins in the late morning.
Therefore the flow of air is from the sea to the land.
C. Mountain Breezes: At night the mountain will cool the air around it
making the air more dense. Therefore the cooler air
will flow into the valleys at night. The narrower the
valley is the stronger the breeze will be.
D. Valley Breezes: During the daytime the mountain air is heated by the land
and therefore rises. The air that is in the valley then will
rise up and replace the less dense air. Creating a breeze
from the valley up into the mountain.
Note: The speed of an uphill movement of air is weaker than the
downward movement of air = mountain breezes are stronger that
valley breezes.