Being a 79 year old woman, I get lots of strange looks when I do something a bit different. Especially when I put my summer sun screen on the OUTSIDE of my windshield. It keeps the windshield cooler, and then when I get in the car, I open the back windows a bit to let the hot air blow out as the air is turned on. It cools my van very quickly. I know they weren’t made to be on the outside, but it just makes sense to this old woman.
Thanks for all the tips we get from your column. Does it make sense to others?
Delores Guhl
Although I don’t put my windshield shade on the outside it makes sense to put it there. Once the sunlight has come through the windshield the heat is INSIDE the vehicle. If you put the shade on the outside the sunlight can’t get through the windshield.
This is why I park in the shade whenever possible.
How do you keep the shade from blowing away?
I put mine on the outside in the winter for frost abatement.
I run the wipers till they’re halfway through the down cycle ( When I start the truck next time the wipers go immediately down to the park position ) then turn off the ignition. The half-mast wipers hold it in place except for the stronger winds.
It’s not so odd to put it outside in the summer, just rare, and more probable to lose it to wind or theft.
I keep it from blowing off by getting the corners inside the door as I shut it, therefore, it is quite secure. My windshield wipers do not stop part way up, so I can’t use them as a holder.
Delores Guhl
You know, that makes more sense than putting it on the inside. I have a 93 Caprice, the windshield is so big I have trouble keeping the shade in place. I think I put it on the outside if it ever stops raining in South Jersey. Thank you for the tip.
Ed B.
This does make more sense----also, you can pick up one at the dollar store, so no big loss if someone swipes it
Doesn’t that sunscreen make the windshield all blury? I bet a lot of dust sticks to it, happens to me at the pool all the time 
You. young lady, have a fine head on your shoulders. What you are doing absolutely does make sense. And a tip my hat to you.
You have a new career calling-this is exactly what the scientists and engineers at NASA in Houston do! You might send them your resume!
Placing the sunshade outside is more effective, but not as convenient. Even more effective (but even less convenient): a full car cover.
If you hold a windshield shade in place with elastic looped around the side mirrors, you’ve got yourself a patentable idea. (Unless someone else has already submitted an application.)
My preferred location when I could keep it on there,makes a lot of sense to me-Kevin