An
anabatic wind, from the
Greek , verbal of
anabainein meaning moving upward, is a warm wind which blows up a steep slope or
mountain side, driven by heating of the slope through
insolation. It is also known as an upslope flow. These winds typically occur during the daytime in calm sunny weather. A
hill or mountain top will be
radiatively warmed by the
Sun which in turn
heats the
air just above it. Air at a similar
altitude over an adjacent
valley or
plain does not get warmed so much because of the greater distance to the ground below it. The effect may be enhanced if the lower lying ground is shaded by the mountain and so receives less heat.