A couple of days ago I tried the Skyrim 1.5 beta patch on steam. I noticed immediately that my screen was covered in transparent lines when looking in certain directions, or being in certain areas of the map.
I can't really take a screenshot of it because it's hard to see unless moving around. Sometimes it's vertical lines across the entire screen, and at some parts it's almost like a very thin layer of ice is covering the screen.

I was hoping this was only going to be an issue in the beta patch but today when my game patched up to 1.5, it was back.

I tried searching around to see if others were having the same problems but it seems I am alone in this.

seems to be an issue with grass shadows causing after effects. I'm getting the same issues

I had the same problem, but I found out that by removing Vurt's Skyrim Flora Overhaul mod, this issue stopped. It seems if you have any grass related mods, they will contradict with the 1.5 patch.
Hope this helps!

turning off Vurt's & lush grass/trees did remove the lines and the shadow flicker, but there is still a hint of a pattern with the vanilla grass - maybe something to do with the official high res textures or the high res fix mod?