|INFLUENCE OF TOPOGRAPHY ON WEATHER
METEOROLOGIST JEFF HABY
Topography has a significant influence on weather. Temperatures and precipitation are influenced by varied terrain. Temperatures
generally decrease with height, thus the higher elevation regions tend to be cooler. However, in particular weather situations
the temperatures can be cooler at the lower elevations. One way this can occur is when a cold front brings shallow cold dense
air into the lower elevations. This is often called cold air damming (see diagram below). The cold air resists climbing the higher
terrain since gravity holds and pushes the denser cold air toward lower elevations. Another way cooler temperatures can occur at
lower elevations is when overnight cooling results in a pooling of cooler air into the lower elevation valleys (see diagram below).
When air flows into higher elevations, lifting will occur on one side of the elevated terrain while sinking will occur on the
other (see diagram below). The side that the lifting occurs is called the windward side. The side that sinking occurs is called
the leeward side. The windward side has more precipitation than the leeward side. The elevated terrain can also act as a lifting
mechanism for precipitation. Precipitation amounts over the course of a year tend to be higher near elevated regions due to
the extra lifting that is generated by air flowing into the high terrain.