An air mass is a big volume of air that has almost the same conditions throughout. And what happens when an air mass is pushed up and over a mountain range
The orographic effect occurs when air masses are pushed to flow across high terrain. As air climbs over mountains, it cools and water vapor condenses. As a consequence, rain is often concentrated on the windward side of mountains, and rainfall increases with elevation in the direction of storm tracks.
Rain, snow, or other precipitation created when moist air is raised as it flows over a mountain range. As the air rises and cools, orographic clouds develop and serve as the source of precipitation, the majority of which falls upwind of the mountain crest.
Because warm air is lighter, it rises when it collides with cold air. It cools at high altitude, and the water vapor it contains condenses. This is referred to as a warm front. It produces nimbostratus clouds, which might cause light rain.
As you ascend a mountain, the air temperature will drop by 6.5 degrees Celsius for every 1000 meters gained. This is referred to as the standard (average) lapse rate.
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