What is Wind Shear?

Wind shear is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal wind shear.

Vertical Wind Shear: change in wind speed or direction with change in height

Horizontal Wind Shear: change in wind speed with a change in lateral position for a given height.

Wind shear is commonly observed near microbursts and downbursts caused by thunderstorms, fronts, areas of locally higher low-level winds referred to as low level jets, near mountains, radiation inversions that occur due to clear skies and calm winds, buildings, wind turbines, and sailboats. Wind shear has significant effects on control of an aircraft, and it has been a sole or contributing cause of many aircraft accidents.

When watching your TV weather forecast, you may hear the meteorologist mention wind shear when talking about severe weather and tornado threats. Strong winds aloft and drastic changes in wind direction with height help lead to tornadoes. The wind shear is what helps to get this column of air to rotate.

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Historical Averages

High Low
Current 46°F 29°F
Average 49°F 31°F
Record 73°F November 21, 1931 17°F November 21, 1951