There is something quite unique that you may actually be able to see on the ground during the total solar eclipse. Strange wavy lines of shadows may start to travel across solid colored surfaces. These eerie phenomenon are known as shadow bands. The effect occurs right before totality and right after. When the small sliver of the Sun casts its light onto the Earth, the light passes through different pockets of air in the upper atmosphere. The air pockets are created by differences in density and temperature, and are the cause of turbulence in airplanes. As the light waves pass through these pockets, their paths can become bent. When they reach the ground, the bent light waves can actually destroy each other in some spots (creating a dark shadow) and become brighter in others. These shadows and bright spots will appear to wiggle around as the air in the sky moves around.
Here is a video showing the shadow bands on the side of a car.
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