Volumetric Clouds shine/flicker through dense fog (Ultra Dynamic Sky) — how to prevent this?

Development Programming & Scripting
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I’m using Ultra Dynamic Sky in a project with runtime-driven, dynamic fog (visual range can change at runtime from clear to very dense). The problem: when fog is dense (e.g. 3m visual range), the background volumetric clouds still shine/flicker through the fog instead of being fully obscured, which looks physically wrong — in real dense fog, distant clouds shouldn’t be visible at all.

Unreal version: 5.2
I am using an separately spawned Exponential Height Fog component, since with other settings or directly using Fog from UDS I was not able to create really dense fog.

I’m open to any solution that fixes this shine-through/flicker, not just hiding the clouds outright. For example:

  1. A way to make height fog properly occlude/obscure the volumetric cloud layer at high density, so clouds are naturally masked instead of shining through.
  2. Alternatively, a supported way to fully hide/disable just the volumetric cloud layer at runtime when visibility is low, while keeping fog, cloud shadows, and sun lighting correct (I do not want to have suddenly a really bright scene even if clouds are set to high opacity).
  3. Any insight into why clouds and height fog don’t composite correctly together at high fog density in the first place — this might point to a rendering order/setting issue I’m missing.

What I’ve tried so far

  • Setting CloudCoverage to 0 — hides clouds but also resets UDS to a “sunny” lighting/fog state.
  • Toggling generic component visibility on sky/cloud actors — hides clouds but also kills the fog.
  • Manually attenuating sun intensity/shadows to fake the effect of clouds without rendering them — inconsistent results vs. actual UDS lighting.
  • Reflection-based access to UDS’s internal “Directional Light Dimming”/cloud shadow functions — partially works but fragile and version-specific.
  • Runtime holdout (SetHoldout) on the cloud component — not exposed in this engine version.
  • Runtime sphere occluder around the camera — visual/material and cloud-shadow-ordering issues, not reliable.
  • Camera far-clip / fog cutoff distance to hide distant clouds — doesn’t work, since clouds/sky render in a separate atmosphere pass independent of scene depth culling.
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clouds show through because volumetric clouds render at sky depth before height fog composites, so 3m fog still doesnt occlude them.

two options: either lower cloud opacity to 0 and lerp sun intensity/fog color yourself instead of letting UDS reset to sunny, or keep clouds and fade them manually. UDS has a SkyAtmosphere + Cloud params you can drive via Set Volumetric Cloud Opacity or by setting CloudCoverage and then reapplying your fog/sun overrides on tick so it doesnt snap back.

also try HeightFog FogDensity * FogHeightFalloff with a very small VolumetricFog ExtinctionScale and disable Volumetric Cloud Shadows when fog is thick, that stops the flicker. hide clouds via material param on the sky dome rather than actor visibility, that keeps fog/lighting intact.