Why Fog Is Relentless in CDDA 0.H Herbert (And What You Can Do About It)
Fog in CDDA 0.H Herbert Is Not Your Imagination
A 5-out-of-7 fog rate isn’t bad luck, and it isn’t your map seed. Players across very different map generations and biomes have reported the same pattern in 0.H Herbert — fog that sticks around through spring and into summer, doesn’t improve when you travel, and makes camera-equipped vehicles nearly useless in built-up areas. There are real, traceable reasons this happens, and a few things you can actually do about it mid-save.
How the Weather Generator Works
CDDA’s weather isn’t drawn from a flat random pool each morning. It uses a weighted transition system — the current weather type influences the probability of what comes next, and those probabilities shift based on the in-game season and the baseline temperature for your starting region. Each weather type is defined in the game’s WEATHER_TYPE JSON, with fields like sight_penalty and ranged_penalty that determine how badly a condition hurts visibility.
The key thing about fog: once the generator lands on fog or light fog, the probability of staying in that state is high. This is intentional — fog in real life doesn’t vanish after an hour. But it means that when the system tips toward fog, it tends to stay there for a while. A single foggy morning can cascade into two or three consecutive foggy days without anything going wrong per se.
Spring and early summer also naturally push the generator toward fog-friendly conditions. Humid climate starting points amplify this. If you started on a temperate or coastal map type, you’re getting both factors stacked at once during the exact window your character is in right now.
What the 0.H Herbert Release Changed
Herbert didn’t ship a targeted fog rework. What it did ship was a large weather-related fix (pull request #82369 in the CleverRaven repository) that corrected an offset in how the weather generator places the midwinter anchor after changes to the internal time_past_new_year calculation. An off-by-a-season error in that anchor can quietly push the generator into fog-heavy temperature windows far more often than intended — which would explain why the fog rate feels wrong even during summer, when it should be easing off.
Whether that fix is in the version you’re running depends on your build. If you’re on the stable 0.H Steam release, that patch may not have landed yet.
Mods That Make It Much Worse
Two scenarios have their own separate fog weighting that stacks on top of the base game tables: No Hope and Innawood. Both have open GitHub issues specifically about excessive fog. No Hope in particular leans on fog as part of its design — it’s harsher in almost every environmental way — but the frequency ends up impractical even by that mod’s own standards. If you’re running either of those, the 5/7 rate you’re seeing isn’t surprising at all, and the base game’s weather fix won’t fully resolve it.
Disabling a mod mid-save won’t retroactively adjust your weather tables, unfortunately. Worth knowing for a fresh run though.
Why Your Death Mobile’s Cameras Stop Working
Vehicle-mounted cameras use the same line-of-sight rules as player vision. Fog’s sight_penalty shrinks effective vision range to just a few tiles. A camera that normally covers a wide arc in front of your vehicle becomes almost useless — you see the tiles directly adjacent and not much more.
There’s an additional asymmetry that was flagged in GitHub issue #66586: monsters in fog retain proportionally better sight than the player does. So fog doesn’t level the playing field. It tilts it. Clearing city blocks with a camera-guided vehicle during fog isn’t just slow — you’re operating at a genuine tactical disadvantage compared to the zombies around you.
What You Can Actually Do About It
- Time your runs around midday. Fog in CDDA reliably burns off as the in-game day progresses. Morning is the worst window; the early afternoon period is typically the clearest. If you wait before moving the vehicle into a dense area, you’ll often get a workable visibility window without changing anything else.
- Supplement cameras with floodlights. Vehicle-mounted headlamps and flood lights illuminate tiles independently of the sight_penalty system — they push light out regardless of fog density. Running them alongside your cameras gives you some tile coverage in front even when camera range has collapsed to almost nothing.
- Check the in-game weather forecast. The debug menu includes a weather display that shows what conditions are forecast for the next stretch of time. It won’t change the frequency, but it lets you plan city runs around clear windows rather than rolling into fog mid-operation.
- Debug weather override as a last resort. If the fog is genuinely breaking your playthrough rather than just annoying you, the debug menu weather override will force-clear it. It persists across reloads, so you need to manually clear it afterward — but it works cleanly and doesn’t corrupt the save.
When Will a Fix Hit Stable?
The weather generator patch in PR #82369 was addressed in the experimental branch. Stable releases on Steam follow a slower cadence than experimental snapshots, so there’s typically a gap between a fix landing in the repository and it reaching most players. Checking the CleverRaven GitHub or the official CDDA forums for the latest experimental build notes is the fastest way to see if the fix is in a version you can switch to.
The fog issue in specific mods like No Hope is a separate track — those need their own JSON-level changes to the weather weighting, which may or may not land alongside the core fix.