diff --git a/Theriapolis.Core/World/Generation/Stages/MoistureGenStage.cs b/Theriapolis.Core/World/Generation/Stages/MoistureGenStage.cs
index 2caae04..aa16c53 100644
--- a/Theriapolis.Core/World/Generation/Stages/MoistureGenStage.cs
+++ b/Theriapolis.Core/World/Generation/Stages/MoistureGenStage.cs
@@ -28,6 +28,10 @@ public sealed class MoistureGenStage : IWorldGenStage
         int W = C.WORLD_WIDTH_TILES;
         int H = C.WORLD_HEIGHT_TILES;
 
+        // FastNoiseLite.EnsurePerm() is not thread-safe; calling GetNoise once here
+        // populates _perm in the main thread before the parallel loop reads it.
+        _ = noise.GetNoise01(0f, 0f);
+
         Parallel.For(0, H, ty =>
         {
             for (int tx = 0; tx < W; tx++)
diff --git a/Theriapolis.Core/World/Generation/Stages/TemperatureGenStage.cs b/Theriapolis.Core/World/Generation/Stages/TemperatureGenStage.cs
index e11d149..4e3f686 100644
--- a/Theriapolis.Core/World/Generation/Stages/TemperatureGenStage.cs
+++ b/Theriapolis.Core/World/Generation/Stages/TemperatureGenStage.cs
@@ -29,6 +29,10 @@ public sealed class TemperatureGenStage : IWorldGenStage
         int W = C.WORLD_WIDTH_TILES;
         int H = C.WORLD_HEIGHT_TILES;
 
+        // FastNoiseLite.EnsurePerm() is not thread-safe; calling GetNoise once here
+        // populates _perm in the main thread before the parallel loop reads it.
+        _ = noise.GetNoise(0f, 0f);
+
         Parallel.For(0, H, ty =>
         {
             // Latitude: 0 at north (cold), 1 at south (warm)