They started to do this when Alpine comes:

The game clearly does not like Alpine.
It looks like an overheating gpu, but it only happens on Alpine, once every ten times or so and the game runs as always after the loading screen.
PS. Why not show an overview of the map from way up, some viewpoint you never get to see ingame? Looking into the sun is too bleak, especially on caustic, where there is almost nothing to see on the leading screen.