What characterizes low-level vertical windshear?

Low-level vertical windshear is characterized by significant changes in wind speed and direction with altitude, particularly within the lowest part of the atmosphere, often influenced by local temperature changes during specific times of the day. This phenomenon commonly occurs overnight and during early mornings due to temperature inversions that develop as the surface cools after sunset. As the ground cools, the air in contact with the surface becomes denser and more stable, which can lead to horizontal windshear as winds higher up in the atmosphere continue to blow at different speeds.

The occurrence during these hours is particularly notable near airports, where changes in wind can greatly impact aircraft performance during takeoff and landing. While summer days may present conditions conducive to other types of windshear, the characteristic low-level windshear is more distinctly tied to the diurnal patterns observed at night and in the early morning. This understanding is crucial for pilots and meteorologists in predicting and mitigating risks associated with low-level windshear.