diff --git a/code/datums/weather/weather.dm b/code/datums/weather/weather.dm
index faee8a3e5e6..b3d9e96743b 100644
--- a/code/datums/weather/weather.dm
+++ b/code/datums/weather/weather.dm
@@ -67,7 +67,8 @@
 	/// If this bit of weather should also draw an overlay that's uneffected by lighting onto the area
 	/// Taken from weather_glow.dmi
 	var/use_glow = TRUE
-	var/list/offsets_to_overlays
+	/// List of all overlays to apply to our turfs
+	var/list/overlay_cache
 
 	/// The stage of the weather, from 1-4
 	var/stage = END_STAGE
@@ -220,62 +221,45 @@
  *
  */
 /datum/weather/proc/update_areas()
-	var/using_icon_state = ""
+	var/list/new_overlay_cache = generate_overlay_cache()
+	for(var/area/impacted as anything in impacted_areas)
+		if(length(overlay_cache))
+			impacted.overlays -= overlay_cache
+		if(length(new_overlay_cache))
+			impacted.overlays += new_overlay_cache
+
+	overlay_cache = new_overlay_cache
+
+/// Returns a list of visual offset -> overlays to use
+/datum/weather/proc/generate_overlay_cache()
+	// We're ending, so no overlays at all
+	if(stage == END_STAGE)
+		return list()
+
+	var/weather_state = ""
 	switch(stage)
 		if(STARTUP_STAGE)
-			using_icon_state = telegraph_overlay
+			weather_state = telegraph_overlay
 		if(MAIN_STAGE)
-			using_icon_state = weather_overlay
+			weather_state = weather_overlay
 		if(WIND_DOWN_STAGE)
-			using_icon_state = end_overlay
-		if(END_STAGE)
-			using_icon_state = ""
+			weather_state = end_overlay
 
-	// Note: what we do here is effectively apply two overlays to each area, for every unique multiz layer they inhabit
-	// One is the base, which will be masked by lighting. the other is "glowing", and provides a nice contrast
-	// This method of applying one overlay per z layer has some minor downsides, in that it could lead to improperly doubled effects if some have alpha
-	// I prefer it to creating 2 extra plane masters however, so it's a cost I'm willing to pay
-	// LU
-	var/list/new_offsets_to_overlays = list()
-	for(var/V in impacted_areas)
-		var/area/N = V
+	// Use all possible offsets
+	// Yes this is a bit annoying, but it's too slow to calculate and store these from turfs, and it shouldn't (I hope) look weird
+	var/list/gen_overlay_cache = list()
+	for(var/offset in 0 to SSmapping.max_plane_offset)
+		// Note: what we do here is effectively apply two overlays to each area, for every unique multiz layer they inhabit
+		// One is the base, which will be masked by lighting. the other is "glowing", and provides a nice contrast
+		// This method of applying one overlay per z layer has some minor downsides, in that it could lead to improperly doubled effects if some have alpha
+		// I prefer it to creating 2 extra plane masters however, so it's a cost I'm willing to pay
+		// LU
+		var/mutable_appearance/glow_overlay = mutable_appearance('icons/effects/glow_weather.dmi', weather_state, overlay_layer, null, ABOVE_LIGHTING_PLANE, 100, offset_const = offset)
+		glow_overlay.color = weather_color
+		gen_overlay_cache += glow_overlay
 
-		// List of overlays this area uses
-		var/list/mutable_appearance/overlays = list()
-		// Use all possible offsets
-		// Yes this is a bit annoying, but it's too slow to calculate and store these, and it shouldn't (I hope) look weird
-		for(var/offset in 0 to SSmapping.max_plane_offset)
-			var/keyd_offset = offset + 1
-			if(length(new_offsets_to_overlays) < keyd_offset)
-				new_offsets_to_overlays.len = keyd_offset
-			var/list/mutable_appearance/existing_appearances = new_offsets_to_overlays[keyd_offset]
-			if(existing_appearances)
-				overlays += existing_appearances
-				continue
-
-			var/list/offset_overlays = list()
-			var/mutable_appearance/glow_overlay = mutable_appearance('icons/effects/glow_weather.dmi', using_icon_state, overlay_layer, N, ABOVE_LIGHTING_PLANE, 100, offset_const = offset)
-			glow_overlay.color = weather_color
-			offset_overlays += glow_overlay
-
-			if(stage != END_STAGE)
-				var/mutable_appearance/weather_overlay = mutable_appearance('icons/effects/weather_effects.dmi', using_icon_state, overlay_layer, plane = overlay_plane, offset_const = offset)
-				weather_overlay.color = weather_color
-				offset_overlays += weather_overlay
-
-			new_offsets_to_overlays[keyd_offset] = offset_overlays
-			overlays += offset_overlays
-
-		var/list/mutable_appearance/old_glows = list()
-		// Offset (ha) by 1 to match the key
-		for(var/offset in 1 to SSmapping.max_plane_offset + 1)
-			if(length(offsets_to_overlays) >= offset)
-				old_glows += offsets_to_overlays[offset]
-
-		if(length(old_glows))
-			N.overlays -= old_glows
-		if(length(overlays))
-			N.overlays += overlays
-
-	offsets_to_overlays = new_offsets_to_overlays
+		var/mutable_appearance/weather_overlay = mutable_appearance('icons/effects/weather_effects.dmi', weather_state, overlay_layer, plane = overlay_plane, offset_const = offset)
+		weather_overlay.color = weather_color
+		gen_overlay_cache += weather_overlay
 
+	return gen_overlay_cache