diff --git a/Source/smokeview/callbacks.c b/Source/smokeview/callbacks.c
index f359a1491..5b0618529 100644
--- a/Source/smokeview/callbacks.c
+++ b/Source/smokeview/callbacks.c
@@ -2278,6 +2278,15 @@ void Keyboard(unsigned char key, int flag){
       }
       else{
         outline_mode++;
+        if(outline_mode == SCENE_OUTLINE_MESH+1){
+          if(meshface_horiz == 0){
+            outline_mode = SCENE_OUTLINE_MESH;
+            meshface_horiz = 1;
+          }
+          else{
+            meshface_horiz = 0;
+          }
+        }
         if(outline_mode!=SCENE_OUTLINE_HIDDEN){
           updatefacelists = 1;
           updatemenu = 1;
@@ -2285,9 +2294,13 @@ void Keyboard(unsigned char key, int flag){
         }
         if(outline_mode>2&&global_scase.noutlineinfo>0)outline_mode=SCENE_OUTLINE_HIDDEN;
         if(outline_mode>1&&global_scase.noutlineinfo==0)outline_mode=SCENE_OUTLINE_HIDDEN;
-        if(outline_mode==SCENE_OUTLINE_HIDDEN)PRINTF("outline mode: hidden\n",outline_mode);
-        if(outline_mode==SCENE_OUTLINE_MESH)PRINTF("outline mode: mesh\n",outline_mode);
-        if(outline_mode==SCENE_OUTLINE_SCENE)PRINTF("outline mode: scene\n",outline_mode);
+        if(outline_mode==SCENE_OUTLINE_HIDDEN)PRINTF("outline mode: hidden\n");
+        if(outline_mode==SCENE_OUTLINE_MESH){
+          PRINTF("outline mode: mesh");
+          if(meshface_horiz==1)PRINTF("(horizontal faces only)");
+          PRINTF("\n");
+        }
+        if(outline_mode==SCENE_OUTLINE_SCENE)PRINTF("outline mode: scene\n");
       }
       break;
     case 'P':
diff --git a/Source/smokeview/drawGeometry.c b/Source/smokeview/drawGeometry.c
index 1280572f8..dfec32784 100644
--- a/Source/smokeview/drawGeometry.c
+++ b/Source/smokeview/drawGeometry.c
@@ -2797,7 +2797,11 @@ void UpdateFaceListsWorker(void){
          (facej->type==BLOCK_outline&&visBlocks==visBLOCKAsInput)||
          ((j>=vent_offset&&j<vent_offset+meshi->nvents)&&vi->isOpenvent==1&&visOpenVentsAsOutline==1)
         ){
-        if(global_scase.obstcoll.nobstinfo==0||(global_scase.obstcoll.nobstinfo>0&&blocklocation==BLOCKlocation_grid))meshi->face_outlines[n_outlines++]=facej;
+        if(global_scase.obstcoll.nobstinfo == 0 ||
+          (global_scase.obstcoll.nobstinfo > 0 && blocklocation == BLOCKlocation_grid)
+          ){
+          if(meshface_horiz == 0 || facej->kmin == facej->kmax)meshi->face_outlines[n_outlines++] = facej;
+        }
         if(visBlocks!=visBLOCKSolidOutline&&visBlocks!=visBLOCKAsInputOutline)continue;
       }
       if(j<vent_offset){
diff --git a/Source/smokeview/glui_display.cpp b/Source/smokeview/glui_display.cpp
index e43901b4f..468fcf97f 100644
--- a/Source/smokeview/glui_display.cpp
+++ b/Source/smokeview/glui_display.cpp
@@ -134,6 +134,7 @@ GLUI_Checkbox *CHECKBOX_user_ticks_show_z=NULL;
 GLUI_Checkbox *CHECKBOX_tick_auto=NULL;
 GLUI_Checkbox *CHECKBOX_label_2=NULL;
 GLUI_Checkbox *CHECKBOX_label_3=NULL;
+GLUI_Checkbox *CHECKBOX_label_4=NULL;
 GLUI_Checkbox *CHECKBOX_labels_flip=NULL;
 GLUI_Checkbox *CHECKBOX_labels_transparent_override=NULL;
 GLUI_Checkbox *CHECKBOX_shownorth = NULL;
@@ -268,6 +269,7 @@ GLUI_Button *BUTTON_label_4=NULL;
 #define LABELS_ticks           8
 #define LABELS_drawface       24
 #define LABELS_hide_overlaps  25
+#define MESH_HORIZ            41
 #define LABELS_version        26
 #define LABELS_meshlabel      27
 #define LABELS_usertick       28
@@ -1035,7 +1037,8 @@ extern "C" void GLUIDisplaySetup(int main_window){
 
   CHECKBOX_label_2=glui_labels->add_checkbox_to_panel(ROLLOUT_general2,"Sort transparent faces",&sort_transparent_faces,LABELS_drawface,GLUILabelsCB);
   CHECKBOX_label_3=glui_labels->add_checkbox_to_panel(ROLLOUT_general2,"Hide overlaps",&hide_overlaps,LABELS_hide_overlaps,GLUILabelsCB);
-
+  CHECKBOX_label_4=glui_labels->add_checkbox_to_panel(ROLLOUT_general2, "Only show horizontal mesh outlines", &meshface_horiz,MESH_HORIZ, GLUILabelsCB);
+  
   if(nface_transparent>0){
     glui_labels->add_column_to_panel(PANEL_gen1,true);
     PANEL_transparency = glui_labels->add_panel_to_panel(ROLLOUT_general2,"Geometry transparency");
@@ -1483,6 +1486,10 @@ extern "C" void GLUILabelsCB(int var){
       colorbar_flip = 1 - colorbar_flip;
       ColorbarMenu(COLORBAR_FLIP);
       break;
+  case MESH_HORIZ:
+    updatefacelists = 1;
+    GLUTPOSTREDISPLAY;
+    break;
   case LABELS_hide_overlaps:
     updatefacelists=1;
     GLUTPOSTREDISPLAY;
diff --git a/Source/smokeview/readsmv.c b/Source/smokeview/readsmv.c
index 1ce020f06..2cc90feec 100644
--- a/Source/smokeview/readsmv.c
+++ b/Source/smokeview/readsmv.c
@@ -3905,11 +3905,12 @@ int ReadIni2(const char *inifile, int localfile){
       continue;
     }
     if(MatchINI(buffer, "MESHVIS") == 1){
-      int nm;
+      int nm, meshface_horiz_input=0;
       meshdata *meshi;
 
       fgets(buffer, 255, stream);
-      sscanf(buffer, "%i", &nm);
+      sscanf(buffer, "%i %i", &nm, &meshface_horiz_input);
+      meshface_horiz = CLAMP(meshface_horiz_input, 0, 1);
       for(i = 0; i<nm; i++){
         if(i>global_scase.meshescoll.nmeshes - 1)break;
         meshi = global_scase.meshescoll.meshinfo + i;
@@ -8076,7 +8077,7 @@ void WriteIni(int flag,char *filename){
   }
   if(global_scase.meshescoll.nmeshes>1){
     fprintf(fileout,"MESHVIS\n");
-    fprintf(fileout," %i\n",global_scase.meshescoll.nmeshes);
+    fprintf(fileout," %i %i\n",global_scase.meshescoll.nmeshes, meshface_horiz);
 
     for(i=0;i<global_scase.meshescoll.nmeshes;i++){
       meshdata *meshi;
diff --git a/Source/smokeview/smokeviewvars.h b/Source/smokeview/smokeviewvars.h
index 29199c8fb..2bc5aa86c 100644
--- a/Source/smokeview/smokeviewvars.h
+++ b/Source/smokeview/smokeviewvars.h
@@ -314,6 +314,7 @@ SVEXTERN char *crender_skips[NRENDER_SKIPS];
 
 SVEXTERN int SVDECL(bounds_each_mesh, 0);
 SVEXTERN int SVDECL(show_bound_diffs, 0);
+SVEXTERN int SVDECL(meshface_horiz, 0);
 
 SVEXTERN slicemenudata SVDECL(*slicemenuinfo, NULL);
 SVEXTERN int SVDECL(generate_info_from_commandline, 0);