People don't understand comfort level vs temperature. When the wind goes away, so does the evaporative cooling effect and the convection effect. So it "feels" much warmer, while the actual dry bulb temperature only slowly increases.
The comfort level will quickly drop off, but that doesn't mean it'll also quickly turn into a dangerous heat situation.
I recommend reading up on wet bulb global temperature. Anyone discussing dry bulb is only telling a very small fraction of the story. As a quick illustration, on a hot day, stand in the shade for a bit. Then move and stand in the sun. Does it feel much warmer? Yes? Well the air temperature is exactly the same, but now you are exposed to direct heat transfer via radiation with the sun.
At the end of the day, it is really the comfort level that you feel and is what can cause heat stroke. In the case of the Skyliners though, I think you get a very sharp increase in WBGT after stopping but it should level off and stay just a little worse than sitting in the shade at the same time. The gondolas are very different than a sealed up car.
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