Pretty sure it has something to do with the performance enhancements, no smoke, no clouds, etc. If I zoomed out far enough it fixed it. So maybe a conflict with zoom-out and the tweaks. Doesn't happen all the time, this is the second time I've had it, other time was at spawn on himmelsdorf encounter, but that time it only happened if I zoomed out to far, could see what looked like a moon.
http://imgur.com/9xtaFaM