diff --git a/data/maps/environment_colors.asm b/data/maps/environment_colors.asm
index aeddb83bc..3497b2b93 100644
--- a/data/maps/environment_colors.asm
+++ b/data/maps/environment_colors.asm
@@ -9,7 +9,7 @@ EnvironmentColorsPointers:
 	dw .IndoorColors  ; GATE
 	dw .DungeonColors ; DUNGEON
 
-; Valid indices: $00 - $29
+; Valid indices: $00 - $29 (see gfx/tilesets/bg_tiles.pal)
 .OutdoorColors:
 	db $00, $01, $02, $28, $04, $05, $06, $07 ; morn
 	db $08, $09, $0a, $28, $0c, $0d, $0e, $0f ; day
diff --git a/data/maps/roofs.asm b/data/maps/roofs.asm
index 2a1b8d3eb..8765cfa6a 100644
--- a/data/maps/roofs.asm
+++ b/data/maps/roofs.asm
@@ -1,36 +1,45 @@
+; MapGroupRoofs values; Roofs indexes
+	const_def
+	const ROOF_NEW_BARK  ; 0
+	const ROOF_VIOLET    ; 1
+	const ROOF_AZALEA    ; 2
+	const ROOF_OLIVINE   ; 3
+	const ROOF_GOLDENROD ; 4
+
 MapGroupRoofs: ; 1c021i
 ; entries correspond to map groups
 ; values are indexes for Roofs (see below)
-	db -1 ; group 0 (unused)
-	db  3 ; group 1 (Olivine)
-	db  2 ; group 2 (Mahogany)
-	db -1 ; group 3
-	db  1 ; group 4 (Ecruteak)
-	db  2 ; group 5 (Blackthorn)
-	db -1 ; group 6
-	db -1 ; group 7
-	db  2 ; group 8 (Azalea)
-	db  2 ; group 9 (Lake of Rage)
-	db  1 ; group 10 (Violet)
-	db  4 ; group 11 (Goldenrod)
-	db -1 ; group 12
-	db -1 ; group 13
-	db -1 ; group 14
-	db -1 ; group 15
-	db -1 ; group 16
-	db -1 ; group 17
-	db -1 ; group 18
-	db  0 ; group 19 (Silver Cave)
-	db -1 ; group 20
-	db -1 ; group 21
-	db  3 ; group 22 (Cianwood)
-	db -1 ; group 23
-	db  0 ; group 24 (New Bark)
-	db -1 ; group 25
-	db  0 ; group 26 (Cherrygrove)
+	db -1             ;  0
+	db ROOF_OLIVINE   ;  1 (Olivine)
+	db ROOF_AZALEA    ;  2 (Mahogany)
+	db -1             ;  3
+	db ROOF_VIOLET    ;  4 (Ecruteak)
+	db ROOF_AZALEA    ;  5 (Blackthorn)
+	db -1             ;  6
+	db -1             ;  7
+	db ROOF_AZALEA    ;  8 (Azalea)
+	db ROOF_AZALEA    ;  9 (Lake of Rage)
+	db ROOF_VIOLET    ; 10 (Violet)
+	db ROOF_GOLDENROD ; 11 (Goldenrod)
+	db -1             ; 12
+	db -1             ; 13
+	db -1             ; 14
+	db -1             ; 15
+	db -1             ; 16
+	db -1             ; 17
+	db -1             ; 18
+	db ROOF_NEW_BARK  ; 19 (Silver Cave)
+	db -1             ; 20
+	db -1             ; 21
+	db ROOF_OLIVINE   ; 22 (Cianwood)
+	db -1             ; 23
+	db ROOF_NEW_BARK  ; 24 (New Bark)
+	db -1             ; 25
+	db ROOF_NEW_BARK  ; 26 (Cherrygrove)
 ; 1c03c
 
 Roofs: ; 1c03c
+; entries correspond to ROOF_* constants
 INCBIN "gfx/tilesets/roofs/0.2bpp"
 INCBIN "gfx/tilesets/roofs/1.2bpp"
 INCBIN "gfx/tilesets/roofs/2.2bpp"
diff --git a/gfx/tilesets/bg_tiles.pal b/gfx/tilesets/bg_tiles.pal
index e21561c74..3605e2184 100644
--- a/gfx/tilesets/bg_tiles.pal
+++ b/gfx/tilesets/bg_tiles.pal
@@ -49,13 +49,5 @@
 	RGB 31,31,16, 31,31,16, 14,09,00, 00,00,00 ; text
 
 ; overworld water
-; morn/day
-	RGB 23, 23, 31
-	RGB 18, 19, 31
-	RGB 13, 12, 31
-	RGB 07, 07, 07
-; nite
-	RGB 15, 13, 27
-	RGB 10, 09, 20
-	RGB 04, 03, 18
-	RGB 00, 00, 00
+	RGB 23,23,31, 18,19,31, 13,12,31, 07,07,07 ; morn/day
+	RGB 15,13,27, 10,09,20, 04,03,18, 00,00,00 ; nite