Wind shear

Subject classification: this is a science resource.

Wind shear is a difference in either wind speed and/or direction over a fairly short distance in the atmosphere. Wind shear can be divided into two different types: horiztontal and vertical wind shear.

NASA schematic of the downward motion of the air until it hits ground.

The situations when the Wind shear is observed happen:

• At weather fronts when the temperature difference across the front is 5 °C or more, and the front moves at 15 kt or faster.
• At low level jets when a significant low level vertical wind shear can develop near the lower portion of the low level jet.
• At mountains when winds blow over and create vertical shear on the lee side.
• At inversions when on a clear and calm night a radiation inversion is formed near the ground.
• At downbursts when an outflow boundary moves away from a thunderstorm.
• At sailing when wind shear affects sailboats by presenting a different wind speed and direction at different heights along the sailing mast.

Other websites

• National Science Digital Library - Wind shear