diff --git a/core/modules/block/js/block.js b/core/modules/block/js/block.js
index 5fa500f..af0e193 100644
--- a/core/modules/block/js/block.js
+++ b/core/modules/block/js/block.js
@@ -99,7 +99,7 @@
         }
 
         // Update the block weights
-        updateBlockweights(table);
+        updateBlockweights(table, regionName);
       };
 
       // Add the behavior to each region select list.
@@ -113,7 +113,7 @@
           table.find('.region-' + select[0].value + '-message').nextUntil('.region-message').last().before(row);
 
           // Update the block weights
-          updateBlockweights(table);
+          updateBlockweights(table, select[0].value);
           // Modify empty regions with added or removed fields.
           checkEmptyRegions(table, row);
           // Remove focus from selectbox.
@@ -121,11 +121,11 @@
         });
       });
 
-      var updateBlockweights = function (table) {
+      var updateBlockweights = function (table, region) {
         // Calculate minimum weight.
         var weight = - Math.round(table.find('.draggable').length / 2);
         // Update the block weights.
-        table.find('.draggable').each(function () {
+        table.find('.region-' + region + '-message').nextUntil('.region-title').each(function () {
             $(this).find('select.block-weight').val(++weight);
           }
         );