Tornado Tim

Tornado Tim - storm chasing and tornadoes




What is Wind Shear?

If you are a storm chaser, you will quickly realize how important wind shear is in tornado producing storms. There are two types of wind shear; directional shear and speed shear. Most tornadoes are spawned from supercell thunderstorms. Supercell thunderstorms are characterized by a persistent rotating updraft and form in environments of strong vertical wind shear. Wind shear is the change in wind speed and/or direction with height.

Directional wind shear image
Directional wind shear image

Directional wind shear is the change in wind direction with height. In the image (left), the view is looking north. The wind near the surface is blowing from the southeast to the northwest.

As the elevation increases the direction veers (changes direction in a clock-wise motion) becoming south, then southwest, and finally, west.

Directional shear can have adverse effects on your DJI drone when flying. Rapid wind shifts can happen from buildings, large objects, hills, so be careful and be sure you are aware of wind changes in your path.

Speed shear Image
Speed shear Image

Speed shear is the change in wind speed with height. In the illustration on the left, the wind is increasing with height. This tends to create a rolling affect to the atmosphere and is believed to be a key component in the formation of mesocyclones which can lead to tornadoes.

Strong vertical shear is the combination of a veering directional shear and strong speed shear and is the condition that is most supportive of supercells.  Thanks to the National Weather Service Jet Stream Online weather school for sharing this information.

Always check the weather before you fly your DJI drone, know the environment you are flying into. Be sure to get the latest ASOS or METAR report so you don’t run into problems from unexpected winds.

Explore the destructive potential of wind shear as it gives rise to a lethal tornado striking Perryton, Texas, in June 2023 as seen in the video below.

Below is a video of a tornado created in a lab experiment.

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