diff --git a/tools/quake3/q3map2/q3map2.h b/tools/quake3/q3map2/q3map2.h
index ee70f226..8bc1c02b 100644
--- a/tools/quake3/q3map2/q3map2.h
+++ b/tools/quake3/q3map2/q3map2.h
@@ -249,7 +249,9 @@ enum class EBrushType
 
 /* ok to increase these at the expense of more memory */
 #define MAX_MAP_AREAS           0x100       /* MAX_MAP_AREA_BYTES in q_shared must match! */
-#define	MAX_MAP_FOGS			0x100			//& 0x100	/* RBSP (32 - world fog - goggles) */
+#define MAX_MAP_FOGS            0x100       /* technically unlimited in engine, but drawsurf sorting code only has 5 bits for fogs */
+#define MAX_IBSP_FOGS           31          /* (2^5 - world fog) */
+#define MAX_RBSP_FOGS           30          /* (2^5 - world fog - goggles) */
 #define MAX_MAP_LEAFS           0x20000
 #define MAX_MAP_PORTALS         0x20000
 #define MAX_MAP_LIGHTING        0x800000
@@ -257,7 +259,7 @@ enum class EBrushType
 #define MAX_MAP_VISCLUSTERS     0x4000 // <= MAX_MAP_LEAFS
 #define MAX_MAP_VISIBILITY      ( VIS_HEADER_SIZE + MAX_MAP_VISCLUSTERS * ( ( ( MAX_MAP_VISCLUSTERS + 63 ) & ~63 ) >> 3 ) )
 
-#define	MAX_MAP_DRAW_SURFS		0x20000
+#define MAX_MAP_DRAW_SURFS      0x20000
 
 #define MAX_MAP_ADVERTISEMENTS  30
 
diff --git a/tools/quake3/q3map2/writebsp.cpp b/tools/quake3/q3map2/writebsp.cpp
index 0995953a..e5108e92 100644
--- a/tools/quake3/q3map2/writebsp.cpp
+++ b/tools/quake3/q3map2/writebsp.cpp
@@ -510,6 +510,12 @@ void EmitFogs( void ){
 			}
 		}
 	}
+
+	/* warn about overflow */
+	if( game->write == WriteIBSPFile && numMapFogs > MAX_IBSP_FOGS )
+		Sys_Warning( "MAX_IBSP_FOGS (%i) exceeded (%i). Visual inconsistencies are expected.\n", MAX_IBSP_FOGS, numMapFogs );
+	if( game->write == WriteRBSPFile && numMapFogs > MAX_RBSP_FOGS )
+		Sys_Warning( "MAX_RBSP_FOGS (%i) exceeded (%i). Visual inconsistencies are expected.\n", MAX_RBSP_FOGS, numMapFogs );
 }