diff --git a/src/openrct2/object/TerrainSurfaceObject.h b/src/openrct2/object/TerrainSurfaceObject.h
index 9663e7d40b..c20df180d2 100644
--- a/src/openrct2/object/TerrainSurfaceObject.h
+++ b/src/openrct2/object/TerrainSurfaceObject.h
@@ -53,7 +53,7 @@ public:
     uint8_t Rotations{};
     money32 Price{};
     TERRAIN_SURFACE_FLAGS Flags{};
-    PaletteIndex MapColours[2];
+    PaletteIndex MapColours[2]{};
 
     void ReadJson(IReadObjectContext* context, json_t& root) override;
     void Load() override;