Displaced landscape vertices not rendering

I am trying to create snow by displacing landscape vertices, using World Displacement in the landscape material. Sometimes the displaced vertices are not rendering, leaving blank space. I guess this is because the actual landscape from which the displaced vertices originate is not rendering because it is no longer visible to the camera, even though it’s displaced vertices are still visible.

I have attached a photo of the landscape not rendering, the problem area is marked with a blue arrow. I have tried to solve this by changing Negative/Positive ZBounds Extension of the landscape, but it did not make a difference.

Just to be clear, this problem appears only on the edge of the screen, where the actual landscape is not visible any more, just the displaced vertices.

If someone wants a sample problem, one is available on this link: [Creating Snow Trails in Unreal Engine 4 | raywenderlich.com][2] (Under downloads: SnowDeformationComplete)

Is there any way i can solve this problem?