This image shows a fog bank in a valley of the Atacama Desert,
along the coast of northern Chile. These fog banks are called
"las camanchacas." Click on image for full size Image Courtesy
of Darryl Scott Extreme Weather in the Southeast Pacific The
weather in the Southeast Pacific region can be considered
extreme, in the sense that it receives very little rainfall and
is extremely dry. For example, some places in the Atacama Desert
in Chile receive an average of less than one millimeter (0.04
inches) of rain a year. Sometimes this region doesn't receive
any rain at all for many years in a row. There are several
reasons why this region is so dry. The Chilean Coastal Range and
the Andes mountains block this area from receiving moisture. In
addition, a large wind current called the Pacific Anticyclone
blows dry air into the region. Finally, an ocean current called
the Humboldt Current brings cool water up the coast of Chile,
which cools the air above it and forms clouds that tend not to
produce precipitation. Ov