Why is there a reverse wind current inside my convertible?

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Fig Neutron
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I was riding home with a friend in their convertible and found that, to my mild irritation, my hair was blowing forward rather than behind me. So, as any logical person would do, I stuck my head out the window to confirm that I wasn’t crazy and my hair should indeed be blowing backwards. After assuring myself that at least some things were still right with the world, I began experimenting with placing my hair in different parts of the car. While all places in the resulted in the same outcome, the forward current seemed to be strongest in the center of the car with very little air flow closer to the window. My initial theory was that the air was whipping around the windshield and somehow causing the current, but putting the windows up had little affect (effect?) on the air flow. My only other idea is that the air coming over the windshield could be the cause, but that doesn’t quite make sense in my mind due to the aerodynamics in the car. Does anyone know the cause of the seemingly reversed current inside of the car?

I noticed this at speeds of about 6-70 mph (or about 11-112 kph). When the speed was any lower it was difficult to be certain of the internal wind’s direction. The car was a Mazda Miata.
 
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Fig Neutron said:
Does anyone know the cause of the seemingly reversed current inside of the car?

The air inside is circulating, because it is interacting with the fast air above. At 2:25 you see this visualized:

 
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