diff --git a/assets/voxygen/shaders/include/point_glow.glsl b/assets/voxygen/shaders/include/point_glow.glsl
index a283447a70..84291cf60b 100644
--- a/assets/voxygen/shaders/include/point_glow.glsl
+++ b/assets/voxygen/shaders/include/point_glow.glsl
@@ -18,7 +18,7 @@ void apply_point_glow_light(Light L, vec3 wpos, vec3 dir, float max_dist, inout
     #if (CLOUD_MODE >= CLOUD_MODE_HIGH)
         vec3 _unused;
         float unused2;
-        float spread = 1.0 / (1.0 + sqrt(cloud_at(nearest, 0.0, _unused, unused2).z) * 0.01);
+        float spread = 1.0 / (1.0 + sqrt(max(cloud_at(nearest, 0.0, _unused, unused2).z, 0.0)) * 0.01);
     #else
         const float spread = 1.0;
     #endif