diff --git a/js/beestat/weather.js b/js/beestat/weather.js
index 0e50ad2..ca61758 100644
--- a/js/beestat/weather.js
+++ b/js/beestat/weather.js
@@ -9,6 +9,8 @@ beestat.weather = {};
  * `icon_color`: UI accent color for the weather icon.
  * `cloud_density`: Controls cloud particle count/intensity in the scene.
  * `cloud_darkness`: Controls cloud shading/dimming (0 clear -> 2 very dark).
+ * `fog_density`: Controls low-altitude volumetric fog cloud density.
+ * `fog_color`: Hex color used to tint low-altitude fog volumes.
  * `rain_density`: Controls rain particle count/intensity.
  * `snow_density`: Controls snow particle count/intensity and snow-cover blend.
  * `lightning_frequency`: Controls frequency/intensity of lightning effects.
@@ -221,6 +223,8 @@ beestat.weather.settings_ = {
     'icon_color': beestat.style.color.gray.base,
     'cloud_density': 0.6,
     'cloud_darkness': 0.2,
+    'fog_density': 1.2,
+    'fog_color': '#d6dde8',
     'rain_density': 0,
     'snow_density': 0,
     'lightning_frequency': 0,
@@ -232,6 +236,8 @@ beestat.weather.settings_ = {
     'icon_color': beestat.style.color.gray.base,
     'cloud_density': 0.45,
     'cloud_darkness': 0.35,
+    'fog_density': 0.8,
+    'fog_color': '#d9d4c8',
     'rain_density': 0,
     'snow_density': 0,
     'lightning_frequency': 0,
@@ -243,6 +249,8 @@ beestat.weather.settings_ = {
     'icon_color': beestat.style.color.gray.base,
     'cloud_density': 0.45,
     'cloud_darkness': 0.35,
+    'fog_density': 1.05,
+    'fog_color': '#cbc7c3',
     'rain_density': 0,
     'snow_density': 0,
     'lightning_frequency': 0,
@@ -254,6 +262,8 @@ beestat.weather.settings_ = {
     'icon_color': beestat.style.color.gray.base,
     'cloud_density': 0.45,
     'cloud_darkness': 0.35,
+    'fog_density': 0.95,
+    'fog_color': '#d9c7a8',
     'rain_density': 0,
     'snow_density': 0,
     'lightning_frequency': 0,
@@ -271,6 +281,8 @@ beestat.weather.default_settings_ = {
   'icon_color': beestat.style.color.gray.base,
   'cloud_density': 0.03,
   'cloud_darkness': 0,
+  'fog_density': 0,
+  'fog_color': '#d6dde8',
   'rain_density': 0,
   'snow_density': 0,
   'lightning_frequency': 0,
@@ -337,6 +349,37 @@ beestat.weather.get_cloud_darkness = function(condition) {
   return beestat.weather.get_settings_(condition).cloud_darkness;
 };
 
+/**
+ * Get fog density for a condition.
+ * Higher values increase low-altitude volumetric fog presence.
+ *
+ * @param {string} condition
+ *
+ * @return {number}
+ */
+beestat.weather.get_fog_density = function(condition) {
+  const fog_density = beestat.weather.get_settings_(condition).fog_density;
+  if (fog_density !== undefined) {
+    return fog_density;
+  }
+  return beestat.weather.default_settings_.fog_density;
+};
+
+/**
+ * Get fog color tint for a condition.
+ *
+ * @param {string} condition
+ *
+ * @return {string}
+ */
+beestat.weather.get_fog_color = function(condition) {
+  const fog_color = beestat.weather.get_settings_(condition).fog_color;
+  if (typeof fog_color === 'string' && fog_color.length > 0) {
+    return fog_color;
+  }
+  return beestat.weather.default_settings_.fog_color;
+};
+
 /**
  * Get rain density for a condition.
  * Higher values increase rain particle count and rainfall intensity.
diff --git a/js/component/card/three_d.js b/js/component/card/three_d.js
index a9f6974..862018d 100644
--- a/js/component/card/three_d.js
+++ b/js/component/card/three_d.js
@@ -76,7 +76,7 @@ beestat.component.card.three_d = function() {
     if (self.get_weather_() !== 'auto') {
       return;
     }
-    self.apply_weather_setting_to_scene_();
+    self.apply_weather_setting_to_scene_(false);
     self.decorate_toolbar_();
   };
   beestat.dispatcher.addEventListener('cache.thermostat', this.handle_thermostat_cache_change_);
@@ -112,6 +112,15 @@ beestat.component.card.three_d.rerender_delay_scene_setting_ms = 1000;
  */
 beestat.component.card.three_d.rerender_loading_min_visible_ms = 350;
 
+/**
+ * Debug-only weather override.
+ * Set to `null` to use the scene-selected weather mode.
+ * Set to a weather condition string (e.g. `fog`, `rain`) to force it.
+ *
+ * @type {?string}
+ */
+beestat.component.card.three_d.debug_weather_override = null;
+
 /**
  * Scene setting keys that require a full rerender.
  *
@@ -666,6 +675,26 @@ beestat.component.card.three_d.prototype.get_auto_weather_from_thermostat_ = fun
   return beestat.weather.get_settings_(thermostat?.weather?.condition).condition;
 };
 
+/**
+ * Get a normalized debug weather override condition.
+ *
+ * @return {?string}
+ */
+beestat.component.card.three_d.prototype.get_debug_weather_override_condition_ = function() {
+  const override = beestat.component.card.three_d.debug_weather_override;
+  if (typeof override !== 'string') {
+    return null;
+  }
+  const normalized_override = override.trim().toLowerCase();
+  if (normalized_override.length === 0) {
+    return null;
+  }
+  if (normalized_override === 'auto') {
+    return this.get_auto_weather_from_thermostat_();
+  }
+  return beestat.weather.get_settings_(normalized_override).condition;
+};
+
 /**
  * Resolve selected weather mode into a weather condition.
  *
@@ -674,6 +703,10 @@ beestat.component.card.three_d.prototype.get_auto_weather_from_thermostat_ = fun
  * @return {string}
  */
 beestat.component.card.three_d.prototype.get_weather_condition_from_mode_ = function(weather) {
+  const debug_override_condition = this.get_debug_weather_override_condition_();
+  if (debug_override_condition !== null) {
+    return debug_override_condition;
+  }
   if (weather === 'auto') {
     return this.get_auto_weather_from_thermostat_();
   }
@@ -798,6 +831,8 @@ beestat.component.card.three_d.prototype.set_show_group_ = function(group_id, vi
  * @return {{
  *   cloud_density: number,
  *   cloud_darkness: number,
+ *   fog_density: number,
+ *   fog_color: string,
  *   rain_density: number,
  *   snow_density: number,
  *   lightning_frequency: number,
@@ -809,6 +844,8 @@ beestat.component.card.three_d.prototype.get_weather_settings_from_weather_ = fu
   return {
     'cloud_density': beestat.weather.get_cloud_density(condition),
     'cloud_darkness': beestat.weather.get_cloud_darkness(condition),
+    'fog_density': beestat.weather.get_fog_density(condition),
+    'fog_color': beestat.weather.get_fog_color(condition),
     'rain_density': beestat.weather.get_rain_density(condition),
     'snow_density': beestat.weather.get_snow_density(condition),
     'lightning_frequency': beestat.weather.get_lightning_frequency(condition),
@@ -818,8 +855,10 @@ beestat.component.card.three_d.prototype.get_weather_settings_from_weather_ = fu
 
 /**
  * Apply current weather settings to the scene.
+ *
+ * @param {boolean=} opt_persist Persist weather settings to floor-plan scene data.
  */
-beestat.component.card.three_d.prototype.apply_weather_setting_to_scene_ = function() {
+beestat.component.card.three_d.prototype.apply_weather_setting_to_scene_ = function(opt_persist) {
   if (this.scene_ === undefined) {
     return;
   }
@@ -827,6 +866,18 @@ beestat.component.card.three_d.prototype.apply_weather_setting_to_scene_ = funct
   this.ensure_scene_settings_values_();
   const weather_settings = this.get_weather_settings_from_weather_(this.get_weather_());
   Object.assign(this.scene_settings_values_, weather_settings);
+  const persist = opt_persist === true;
+  if (persist === true) {
+    const scene_visualize = this.get_scene_visualize_state_();
+    if (scene_visualize !== null) {
+      const previous_settings_json = JSON.stringify(scene_visualize.settings || {});
+      Object.assign(scene_visualize.settings, weather_settings);
+      const next_settings_json = JSON.stringify(scene_visualize.settings);
+      if (previous_settings_json !== next_settings_json) {
+        this.save_scene_visualize_state_();
+      }
+    }
+  }
   this.scene_.set_scene_settings(weather_settings, {
     'rerender': false
   });
@@ -871,10 +922,6 @@ beestat.component.card.three_d.prototype.ensure_scene_settings_values_ = functio
       this.save_scene_visualize_state_();
     }
   }
-  Object.assign(
-    this.scene_settings_values_,
-    this.get_weather_settings_from_weather_(this.get_weather_())
-  );
 };
 
 /**
@@ -1205,6 +1252,7 @@ beestat.component.card.three_d.prototype.decorate_scene_settings_panel_ = functi
   add_section_title('Weather');
   add_number_setting(get_title_case_label('cloud_density'), 'cloud_density', 0, 2, 0.1);
   add_number_setting(get_title_case_label('cloud_darkness'), 'cloud_darkness', 0, 2, 0.1);
+  add_number_setting(get_title_case_label('fog_density'), 'fog_density', 0, 2, 0.1);
   add_number_setting(get_title_case_label('rain_density'), 'rain_density', 0, 2, 0.1);
   add_number_setting(get_title_case_label('snow_density'), 'snow_density', 0, 2, 0.1);
   add_number_setting(get_title_case_label('lightning_frequency'), 'lightning_frequency', 0, 2, 0.1);
@@ -1960,7 +2008,7 @@ beestat.component.card.three_d.prototype.decorate_toolbar_ = function(parent) {
           tile.addEventListener('click', (e) => {
             e.stopPropagation();
             this.set_weather_(mode.value);
-            this.apply_weather_setting_to_scene_();
+            this.apply_weather_setting_to_scene_(true);
             this.weather_menu_open_ = false;
             this.decorate_toolbar_();
           });
@@ -1981,7 +2029,7 @@ beestat.component.card.three_d.prototype.decorate_toolbar_ = function(parent) {
         auto_tile.addEventListener('click', (e) => {
           e.stopPropagation();
           this.set_weather_('auto');
-          this.apply_weather_setting_to_scene_();
+          this.apply_weather_setting_to_scene_(true);
           this.weather_menu_open_ = false;
           this.decorate_toolbar_();
         });
diff --git a/js/component/scene.js b/js/component/scene.js
index bfd803e..7bdee37 100644
--- a/js/component/scene.js
+++ b/js/component/scene.js
@@ -90,6 +90,13 @@ beestat.component.scene.weather_snow_max_count = 1500;
  */
 beestat.component.scene.weather_cloud_max_count = 140;
 
+/**
+ * Maximum low-altitude fog volume sprite count at full fog intensity.
+ *
+ * @type {number}
+ */
+beestat.component.scene.weather_fog_max_count = 18;
+
 /**
  * Time in seconds for weather effects to fully transition to a new mode.
  *
@@ -222,16 +229,18 @@ beestat.component.scene.sidereal_day_seconds = 86164.0905;
 beestat.component.scene.star_drift_visual_factor = 0.12;
 
 /**
- * Runtime scene settings exposed through the scene settings panel.
+ * Runtime scene settings used by environment rendering.
  *
  * @type {{
  *   cloud_density: number,
  *   cloud_darkness: number,
+ *   fog_density: number,
  *   rain_density: number,
  *   snow_density: number,
  *   lightning_frequency: number,
  *   wind_speed: number,
  *   wind_direction: number,
+ *   fog_color: string,
  *   tree_wobble: boolean,
  *   tree_enabled: boolean,
  *   star_density: number,
@@ -243,11 +252,13 @@ beestat.component.scene.star_drift_visual_factor = 0.12;
 beestat.component.scene.default_settings = {
   'cloud_density': 1,
   'cloud_darkness': 0,
+  'fog_density': 0,
   'rain_density': 1,
   'snow_density': 1,
   'lightning_frequency': 0,
   'wind_speed': 0.4,
   'wind_direction': 0,
+  'fog_color': '#d6dde8',
   'tree_wobble': true,
   'tree_enabled': true,
   'star_density': 1,
@@ -465,6 +476,11 @@ beestat.component.scene.prototype.reset_runtime_scene_references_for_rerender_ =
   delete this.snow_particles_;
   delete this.cloud_sprites_;
   delete this.cloud_motion_;
+  delete this.fog_sprites_;
+  delete this.fog_motion_;
+  delete this.fog_bounds_;
+  delete this.current_fog_count_;
+  delete this.current_fog_density_;
   delete this.weather_profile_target_;
   delete this.weather_transition_start_profile_;
   delete this.lightning_flash_light_;
@@ -1346,6 +1362,9 @@ beestat.component.scene.prototype.dispose = function() {
   if (this.cloud_texture_ !== undefined) {
     this.cloud_texture_.dispose();
   }
+  if (this.fog_volume_texture_ !== undefined) {
+    this.fog_volume_texture_.dispose();
+  }
   if (this.moon_phase_texture_ !== undefined) {
     this.moon_phase_texture_.dispose();
   }
diff --git a/js/component/scene/environment.js b/js/component/scene/environment.js
index 720ada8..b5d48e4 100644
--- a/js/component/scene/environment.js
+++ b/js/component/scene/environment.js
@@ -210,7 +210,8 @@ beestat.component.scene.prototype.add_environment_ = function() {
     if (index === 0) {
       mesh.userData.is_ground = true;
     }
-    mesh.receiveShadow = true;
+    mesh.castShadow = true;
+    mesh.receiveShadow = index === 0;
 
     this.environment_group_.add(mesh);
     current_z += stratum.thickness;
diff --git a/js/component/scene/texture.js b/js/component/scene/texture.js
index 1be7f56..ac4def8 100644
--- a/js/component/scene/texture.js
+++ b/js/component/scene/texture.js
@@ -251,6 +251,49 @@ beestat.component.scene.prototype.create_cloud_texture_ = function() {
 };
 
 
+/**
+ * Create a broad soft texture used for low-altitude fog volume sprites.
+ *
+ * @return {THREE.Texture}
+ */
+beestat.component.scene.prototype.create_fog_volume_texture_ = function() {
+  const size = 320;
+  const canvas = document.createElement('canvas');
+  canvas.width = size;
+  canvas.height = size;
+  const context = canvas.getContext('2d');
+
+  const lobes = [
+    {'x': 0.26, 'y': 0.56, 'r': 0.27, 'alpha': 0.5},
+    {'x': 0.46, 'y': 0.5, 'r': 0.3, 'alpha': 0.6},
+    {'x': 0.66, 'y': 0.57, 'r': 0.28, 'alpha': 0.54},
+    {'x': 0.52, 'y': 0.67, 'r': 0.31, 'alpha': 0.42}
+  ];
+
+  lobes.forEach(function(lobe) {
+    const gradient = context.createRadialGradient(
+      size * lobe.x,
+      size * lobe.y,
+      0,
+      size * lobe.x,
+      size * lobe.y,
+      size * lobe.r
+    );
+    gradient.addColorStop(0.0, `rgba(255,255,255,${lobe.alpha})`);
+    gradient.addColorStop(0.55, `rgba(245,249,255,${lobe.alpha * 0.5})`);
+    gradient.addColorStop(1.0, 'rgba(245,249,255,0.0)');
+    context.fillStyle = gradient;
+    context.beginPath();
+    context.arc(size * lobe.x, size * lobe.y, size * lobe.r, 0, Math.PI * 2);
+    context.fill();
+  });
+
+  const texture = new THREE.CanvasTexture(canvas);
+  texture.needsUpdate = true;
+  return texture;
+};
+
+
 /**
  * Draw the moon phase into the reusable moon canvas texture.
  *
diff --git a/js/component/scene/weather.js b/js/component/scene/weather.js
index bbd9251..81f92f6 100644
--- a/js/component/scene/weather.js
+++ b/js/component/scene/weather.js
@@ -18,6 +18,8 @@ beestat.component.scene.prototype.get_weather_design_count_ = function(density_k
     return Math.max(1, Number(beestat.component.scene.weather_rain_max_count || 1));
   case 'snow_density':
     return Math.max(1, Number(beestat.component.scene.weather_snow_max_count || 1));
+  case 'fog_density':
+    return Math.max(1, Number(beestat.component.scene.weather_fog_max_count || 1));
   default:
     return 1;
   }
@@ -69,6 +71,9 @@ beestat.component.scene.prototype.get_weather_count_from_density_ = function(den
 beestat.component.scene.prototype.get_weather_profile_ = function() {
   return {
     'cloud_count': this.get_weather_count_from_density_('cloud_density'),
+    // Fog uses fixed sprite population; density controls opacity.
+    'fog_count': this.get_weather_design_capacity_count_('fog_density'),
+    'fog_density': Math.max(0, Math.min(2, Number(this.get_scene_setting_('fog_density') || 0))),
     'rain_count': this.get_weather_count_from_density_('rain_density'),
     'snow_count': this.get_weather_count_from_density_('snow_density')
   };
@@ -113,6 +118,22 @@ beestat.component.scene.prototype.get_cloud_color_ = function() {
   return base_color.lerp(dark_gray_color, blend);
 };
 
+/**
+ * Get low-altitude fog volume sprite tint color.
+ *
+ * @return {THREE.Color}
+ */
+beestat.component.scene.prototype.get_fog_color_ = function() {
+  const fog_color = this.get_scene_setting_('fog_color');
+  if (
+    typeof fog_color === 'string' ||
+    typeof fog_color === 'number'
+  ) {
+    return new THREE.Color(fog_color);
+  }
+  return new THREE.Color(beestat.component.scene.default_settings.fog_color);
+};
+
 
 /**
  * Update weather transition targets based on appearance weather.
@@ -122,6 +143,8 @@ beestat.component.scene.prototype.update_weather_targets_ = function() {
 
   this.weather_transition_start_profile_ = {
     'cloud_count': this.current_cloud_count_ === undefined ? 0 : this.current_cloud_count_,
+    'fog_count': this.current_fog_count_ === undefined ? 0 : this.current_fog_count_,
+    'fog_density': this.current_fog_density_ === undefined ? 0 : this.current_fog_density_,
     'rain_count': this.current_rain_count_ === undefined ? 0 : this.current_rain_count_,
     'snow_count': this.current_snow_count_ === undefined ? 0 : this.current_snow_count_
   };
@@ -130,7 +153,7 @@ beestat.component.scene.prototype.update_weather_targets_ = function() {
 
 
 /**
- * Get current snow cover blend amount (0-1) from precipitation transition.
+ * Get current snow cover blend amount (0-2) from precipitation transition.
  *
  * @return {number}
  */
@@ -146,7 +169,7 @@ beestat.component.scene.prototype.get_snow_cover_blend_ = function() {
   return Math.max(
     0,
     Math.min(
-      1,
+      2,
       this.current_snow_count_ / configured_snow_count
     )
   );
@@ -165,14 +188,16 @@ beestat.component.scene.prototype.update_snow_surface_colors_ = function(snow_bl
 
   // Keep a small amount of base color visible at peak snow for definition.
   const normalized_blend = Math.max(0, Math.min(1, snow_blend));
+  const grass_normalized_blend = Math.max(0, Math.min(1, snow_blend * 0.5));
   const blend = normalized_blend * 0.9;
+  const grass_blend = grass_normalized_blend * 0.9;
   const foliage_blend = normalized_blend * 0.75;
   const snow_color = new THREE.Color(beestat.component.scene.snow_surface_color);
   const base_roof_color = new THREE.Color(this.get_appearance_value_('roof_color'));
   const base_ground_color = new THREE.Color(this.get_appearance_value_('ground_color'));
 
   const roof_color = base_roof_color.clone().lerp(snow_color, blend);
-  const ground_color = base_ground_color.clone().lerp(snow_color, blend);
+  const ground_color = base_ground_color.clone().lerp(snow_color, grass_blend);
 
   if (this.layers_.roof !== undefined) {
     this.layers_.roof.traverse(function(object) {
@@ -287,7 +312,8 @@ beestat.component.scene.prototype.create_precipitation_system_ = function(bounds
     'static_opacity': config.static_opacity === true,
     'max_wind_angle': config.max_wind_angle || 0,
     'max_wind_speed_scale': config.max_wind_speed_scale || 2,
-    'wind_motion_multiplier': config.wind_motion_multiplier || 1
+    'wind_motion_multiplier': config.wind_motion_multiplier || 1,
+    'wind_speed_curve': config.wind_speed_curve || 'linear'
   };
 };
 
@@ -357,13 +383,21 @@ beestat.component.scene.prototype.update_precipitation_system_ = function(
   );
   const wind_speed_scale = 1 + ((clamped_wind_speed / 2) * (max_wind_speed_scale - 1));
   const wind_motion_multiplier = Math.max(0, Number(precipitation.wind_motion_multiplier || 1));
+  const wind_speed_curve_scale = precipitation.wind_speed_curve === 'half_same_double'
+    ? Math.pow(2, clamped_wind_speed - 1)
+    : 1;
   const direction_velocity_x = horizontal_scale * wind_x;
   const direction_velocity_y = horizontal_scale * wind_y;
   const direction_velocity_z = vertical_scale;
 
   for (let i = 0; i < clamped_count; i++) {
     const offset = i * 3;
-    const speed = precipitation.speeds[i] * delta_seconds * wind_speed_scale * wind_motion_multiplier;
+    const speed =
+      precipitation.speeds[i] *
+      delta_seconds *
+      wind_speed_scale *
+      wind_motion_multiplier *
+      wind_speed_curve_scale;
     positions[offset + 2] += speed * direction_velocity_z;
     positions[offset] += speed * direction_velocity_x;
     positions[offset + 1] += speed * direction_velocity_y;
@@ -688,6 +722,9 @@ beestat.component.scene.prototype.add_weather_ = function(center_x, center_y, pl
   if (this.cloud_texture_ === undefined) {
     this.cloud_texture_ = this.create_cloud_texture_();
   }
+  if (this.fog_volume_texture_ === undefined) {
+    this.fog_volume_texture_ = this.create_fog_volume_texture_();
+  }
 
   if (this.snow_particle_texture_ === undefined) {
     this.snow_particle_texture_ = this.create_snow_particle_texture_();
@@ -761,6 +798,65 @@ beestat.component.scene.prototype.add_weather_ = function(center_x, center_y, pl
     });
   }
 
+  const fog_capacity = this.get_weather_design_capacity_count_('fog_density', this.weather_area_);
+  const fog_bounds = {
+    'min_x': bounds.min_x - 140,
+    'max_x': bounds.max_x + 140,
+    'min_y': bounds.min_y - 140,
+    'max_y': bounds.max_y + 140,
+    // Keep fog cards well above the ground plane to avoid seam artifacts.
+    'min_z': -420,
+    'max_z': -120
+  };
+
+  this.fog_bounds_ = fog_bounds;
+  this.fog_sprites_ = [];
+  this.fog_motion_ = [];
+
+  // Pre-build low-altitude volumetric fog sprites.
+  for (let i = 0; i < fog_capacity; i++) {
+    const fog_material = new THREE.SpriteMaterial({
+      'map': this.fog_volume_texture_,
+      'color': 0xd6dde8,
+      'transparent': true,
+      'opacity': 0,
+      'depthWrite': false,
+      'depthTest': true
+    });
+
+    const fog = new THREE.Sprite(fog_material);
+    fog.position.set(
+      fog_bounds.min_x + Math.random() * (fog_bounds.max_x - fog_bounds.min_x),
+      fog_bounds.min_y + Math.random() * (fog_bounds.max_y - fog_bounds.min_y),
+      fog_bounds.min_z + Math.random() * (fog_bounds.max_z - fog_bounds.min_z)
+    );
+    const fog_size = 680 + Math.random() * 980;
+    fog.scale.set(fog_size * 1.7, fog_size * 0.45, 1);
+    fog.layers.set(beestat.component.scene.layer_visible);
+    fog.userData.is_environment = true;
+    this.weather_group_.add(fog);
+    this.fog_sprites_.push(fog);
+    this.fog_motion_.push({
+      'base_x': fog.position.x,
+      'base_y': fog.position.y,
+      'base_z': fog.position.z,
+      'base_scale_x': fog.scale.x,
+      'base_scale_y': fog.scale.y,
+      'base_opacity': 0.34 + (Math.random() * 0.12),
+      'phase': Math.random() * Math.PI * 2,
+      'pulse_speed': 0.12 + (Math.random() * 0.1),
+      'scale_wobble_x': 0.03 + (Math.random() * 0.02),
+      'scale_wobble_y': 0.02 + (Math.random() * 0.02),
+      'opacity_wobble': 0.04 + (Math.random() * 0.03),
+      'wiggle_x': 18 + (Math.random() * 26),
+      'wiggle_y': 16 + (Math.random() * 24),
+      'wiggle_z': 4 + (Math.random() * 8),
+      'wiggle_freq_x': 0.55 + (Math.random() * 0.4),
+      'wiggle_freq_y': 0.45 + (Math.random() * 0.35),
+      'wiggle_freq_z': 0.35 + (Math.random() * 0.3)
+    });
+  }
+
   // Build precipitation systems (rain and snow) at design-capacity scale.
   this.rain_particles_ = this.create_precipitation_system_(
     bounds,
@@ -773,8 +869,8 @@ beestat.component.scene.prototype.add_weather_ = function(center_x, center_y, pl
       'color': 0xa8c7ff,
       'opacity': 0.5,
       'static_opacity': true,
-      'speed_min': 280,
-      'speed_max': 430,
+      'speed_min': 560,
+      'speed_max': 860,
       'drift': 28,
       'texture': this.rain_particle_texture_,
       'max_wind_angle': 45,
@@ -799,7 +895,8 @@ beestat.component.scene.prototype.add_weather_ = function(center_x, center_y, pl
       'texture': this.snow_particle_texture_,
       'max_wind_angle': 75,
       'max_wind_speed_scale': 3,
-      'wind_motion_multiplier': 2.5
+      'wind_motion_multiplier': 2.5,
+      'wind_speed_curve': 'half_same_double'
     }
   );
   this.weather_group_.add(this.snow_particles_.points);
@@ -816,6 +913,8 @@ beestat.component.scene.prototype.add_weather_ = function(center_x, center_y, pl
   const initial_weather_profile = this.get_weather_profile_();
   this.weather_profile_target_ = initial_weather_profile;
   this.current_cloud_count_ = initial_weather_profile.cloud_count;
+  this.current_fog_count_ = initial_weather_profile.fog_count;
+  this.current_fog_density_ = initial_weather_profile.fog_density;
   this.current_rain_count_ = initial_weather_profile.rain_count;
   this.current_snow_count_ = initial_weather_profile.snow_count;
   this.update_weather_targets_();
@@ -852,6 +951,8 @@ beestat.component.scene.prototype.update_weather_ = function() {
   if (this.weather_transition_start_profile_ === undefined) {
     this.weather_transition_start_profile_ = {
       'cloud_count': this.current_cloud_count_ === undefined ? 0 : this.current_cloud_count_,
+      'fog_count': this.current_fog_count_ === undefined ? 0 : this.current_fog_count_,
+      'fog_density': this.current_fog_density_ === undefined ? 0 : this.current_fog_density_,
       'rain_count': this.current_rain_count_ === undefined ? 0 : this.current_rain_count_,
       'snow_count': this.current_snow_count_ === undefined ? 0 : this.current_snow_count_
     };
@@ -880,6 +981,14 @@ beestat.component.scene.prototype.update_weather_ = function() {
     this.weather_transition_start_profile_.cloud_count,
     this.weather_profile_target_.cloud_count
   );
+  this.current_fog_count_ = transition(
+    this.weather_transition_start_profile_.fog_count,
+    this.weather_profile_target_.fog_count
+  );
+  this.current_fog_density_ = transition(
+    this.weather_transition_start_profile_.fog_density,
+    this.weather_profile_target_.fog_density
+  );
   this.current_rain_count_ = transition(
     this.weather_transition_start_profile_.rain_count,
     this.weather_profile_target_.rain_count
@@ -940,6 +1049,51 @@ beestat.component.scene.prototype.update_weather_ = function() {
     }
   }
 
+  // Update low-altitude volumetric fog sprites.
+  if (this.fog_sprites_ !== undefined && this.fog_motion_ !== undefined) {
+    const now_seconds = now_ms / 1000;
+    const fog_color = this.get_fog_color_();
+    const fog_density = Math.max(
+      0,
+      Math.min(
+        1,
+        (this.current_fog_density_ === undefined ? 0 : this.current_fog_density_) / 2
+      )
+    );
+
+    for (let i = 0; i < this.fog_sprites_.length; i++) {
+      const sprite = this.fog_sprites_[i];
+      const motion = this.fog_motion_[i];
+      const phase = now_seconds * motion.pulse_speed + motion.phase;
+
+      const scale_x_wobble = 1 + (Math.sin(phase) * motion.scale_wobble_x);
+      const scale_y_wobble = 1 + (Math.cos(phase * 0.88) * motion.scale_wobble_y);
+      const fog_scale_transition = 0.62 + (0.38 * fog_density);
+      sprite.scale.set(
+        motion.base_scale_x * scale_x_wobble * fog_scale_transition,
+        motion.base_scale_y * scale_y_wobble * fog_scale_transition,
+        1
+      );
+
+      sprite.position.x = motion.base_x + Math.sin(phase * motion.wiggle_freq_x) * motion.wiggle_x;
+      sprite.position.y = motion.base_y + Math.cos(phase * motion.wiggle_freq_y) * motion.wiggle_y;
+      sprite.position.z = motion.base_z + Math.sin(phase * motion.wiggle_freq_z) * motion.wiggle_z;
+
+      if (sprite.material !== undefined) {
+        if (sprite.material.color !== undefined) {
+          sprite.material.color.copy(fog_color);
+        }
+        sprite.material.opacity = Math.max(
+          0,
+          Math.min(
+            1,
+            (motion.base_opacity + Math.sin(phase * 0.61) * motion.opacity_wobble) * fog_density
+          )
+        );
+      }
+    }
+  }
+
   // Update precipitation + lightning systems, then re-apply snow cover tinting.
   this.update_precipitation_system_(
     this.rain_particles_,