I washed my car yesterday - an overcast day. I used a new microfiber towel to dry. On the windshield I more or less just wiped it semi-dry figuring I the wipers would take car of the water. I ended up with very small round tan circles of water spots. Enough that when driving it looked like a haze from inside. No other windows had a problem and yes I washed and rinsed the car thoroughly.

I tried Windex and Invisible Foaming window cleaner and neither made a dent in removing the spots. Everything went through my mind to use - from rubbing compound to Soft Scrub but the last thing I wanted to do is make it worse by scratching the glass.

I tried our cooktop glass cleaner and the window never looked better to the point I noticed a new rock chip. The best thing is it is easy to use. Used a clean cloth to rub it on (gently) until a slight haze was left. Then used another cloth to wipe off the residue. There was absolutely no film left. The windshield wipers work much better now. I am even considering using it on the inside of the front windshield since I can never truly get the film off when using glass cleaner. The brand I used was Weiman Glass Cook Top Cleaner.

 

Great tip! I am going to try it on one of our cars.

 

Note - I will not do outside front sides since the car has the Teflon coating that came with the cold weather package (I think that is the package) and nor will I do it on the inside rear since do not want to mess the rear window defogger and radio antenna lines.

 

You can also try using a water and vinegar solution

 

@dougm213 - on my previous Lexus, I had tried this to get rid of a water spot that refused to go away. It worked. But I noticed after that that there was a noticeable difference in how water was repelled from that area while I was washing the car. It didn't bead off as well as the other (untreated) areas.
I think the windshield (at least the outer side) also has some type of water repellent coating - not sure if it is the same as what is on the front windows.

In case you notice that, just use a water repellent like rainx or enduroshielf over the entire windshield. That worked for me.