diff --git a/world_clocks/package-lock.json b/world_clocks/package-lock.json
index 36dbe08..45f9498 100644
--- a/world_clocks/package-lock.json
+++ b/world_clocks/package-lock.json
@@ -2874,7 +2874,8 @@
             },
             "ansi-regex": {
               "version": "2.1.1",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "aproba": {
               "version": "1.2.0",
@@ -2892,11 +2893,13 @@
             },
             "balanced-match": {
               "version": "1.0.0",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "brace-expansion": {
               "version": "1.1.11",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "balanced-match": "^1.0.0",
                 "concat-map": "0.0.1"
@@ -2909,15 +2912,18 @@
             },
             "code-point-at": {
               "version": "1.1.0",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "concat-map": {
               "version": "0.0.1",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "console-control-strings": {
               "version": "1.1.0",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "core-util-is": {
               "version": "1.0.2",
@@ -3020,7 +3026,8 @@
             },
             "inherits": {
               "version": "2.0.3",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "ini": {
               "version": "1.3.5",
@@ -3030,6 +3037,7 @@
             "is-fullwidth-code-point": {
               "version": "1.0.0",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "number-is-nan": "^1.0.0"
               }
@@ -3042,17 +3050,20 @@
             "minimatch": {
               "version": "3.0.4",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "brace-expansion": "^1.1.7"
               }
             },
             "minimist": {
               "version": "0.0.8",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "minipass": {
               "version": "2.3.5",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "safe-buffer": "^5.1.2",
                 "yallist": "^3.0.0"
@@ -3069,6 +3080,7 @@
             "mkdirp": {
               "version": "0.5.1",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "minimist": "0.0.8"
               }
@@ -3141,7 +3153,8 @@
             },
             "number-is-nan": {
               "version": "1.0.1",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "object-assign": {
               "version": "4.1.1",
@@ -3151,6 +3164,7 @@
             "once": {
               "version": "1.4.0",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "wrappy": "1"
               }
@@ -3226,7 +3240,8 @@
             },
             "safe-buffer": {
               "version": "5.1.2",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "safer-buffer": {
               "version": "2.1.2",
@@ -3256,6 +3271,7 @@
             "string-width": {
               "version": "1.0.2",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "code-point-at": "^1.0.0",
                 "is-fullwidth-code-point": "^1.0.0",
@@ -3273,6 +3289,7 @@
             "strip-ansi": {
               "version": "3.0.1",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "ansi-regex": "^2.0.0"
               }
@@ -3311,11 +3328,13 @@
             },
             "wrappy": {
               "version": "1.0.2",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "yallist": {
               "version": "3.0.3",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             }
           }
         },
@@ -6838,7 +6857,8 @@
             },
             "ansi-regex": {
               "version": "2.1.1",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "aproba": {
               "version": "1.2.0",
@@ -6856,11 +6876,13 @@
             },
             "balanced-match": {
               "version": "1.0.0",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "brace-expansion": {
               "version": "1.1.11",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "balanced-match": "^1.0.0",
                 "concat-map": "0.0.1"
@@ -6873,15 +6895,18 @@
             },
             "code-point-at": {
               "version": "1.1.0",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "concat-map": {
               "version": "0.0.1",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "console-control-strings": {
               "version": "1.1.0",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "core-util-is": {
               "version": "1.0.2",
@@ -6984,7 +7009,8 @@
             },
             "inherits": {
               "version": "2.0.3",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "ini": {
               "version": "1.3.5",
@@ -6994,6 +7020,7 @@
             "is-fullwidth-code-point": {
               "version": "1.0.0",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "number-is-nan": "^1.0.0"
               }
@@ -7006,17 +7033,20 @@
             "minimatch": {
               "version": "3.0.4",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "brace-expansion": "^1.1.7"
               }
             },
             "minimist": {
               "version": "0.0.8",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "minipass": {
               "version": "2.3.5",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "safe-buffer": "^5.1.2",
                 "yallist": "^3.0.0"
@@ -7033,6 +7063,7 @@
             "mkdirp": {
               "version": "0.5.1",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "minimist": "0.0.8"
               }
@@ -7105,7 +7136,8 @@
             },
             "number-is-nan": {
               "version": "1.0.1",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "object-assign": {
               "version": "4.1.1",
@@ -7115,6 +7147,7 @@
             "once": {
               "version": "1.4.0",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "wrappy": "1"
               }
@@ -7190,7 +7223,8 @@
             },
             "safe-buffer": {
               "version": "5.1.2",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "safer-buffer": {
               "version": "2.1.2",
@@ -7220,6 +7254,7 @@
             "string-width": {
               "version": "1.0.2",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "code-point-at": "^1.0.0",
                 "is-fullwidth-code-point": "^1.0.0",
@@ -7237,6 +7272,7 @@
             "strip-ansi": {
               "version": "3.0.1",
               "bundled": true,
+              "optional": true,
               "requires": {
                 "ansi-regex": "^2.0.0"
               }
@@ -7275,11 +7311,13 @@
             },
             "wrappy": {
               "version": "1.0.2",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             },
             "yallist": {
               "version": "3.0.3",
-              "bundled": true
+              "bundled": true,
+              "optional": true
             }
           }
         }
@@ -8302,9 +8340,9 @@
       "integrity": "sha512-bV7f+6l2QigeBBZSM/6yTNq4P2fNpSWj/0e7jQcy87A8e7o2nAfP/34/2ky5Vw4B9S446EtIhodAzkFCcR4dQg=="
     },
     "moment-timezone": {
-      "version": "0.5.25",
-      "resolved": "https://registry.npmjs.org/moment-timezone/-/moment-timezone-0.5.25.tgz",
-      "integrity": "sha512-DgEaTyN/z0HFaVcVbSyVCUU6HeFdnNC3vE4c9cgu2dgMTvjBUBdBzWfasTBmAW45u5OIMeCJtU8yNjM22DHucw==",
+      "version": "0.5.35",
+      "resolved": "https://registry.npmjs.org/moment-timezone/-/moment-timezone-0.5.35.tgz",
+      "integrity": "sha512-cY/pBOEXepQvlgli06ttCTKcIf8cD1nmNwOKQQAdHBqYApQSpAqotBMX0RJZNgMp6i0PlZuf1mFtnlyEkwyvFw==",
       "requires": {
         "moment": ">= 2.9.0"
       }
diff --git a/world_clocks/package.json b/world_clocks/package.json
index fef68e1..1757c8e 100644
--- a/world_clocks/package.json
+++ b/world_clocks/package.json
@@ -6,7 +6,7 @@
     "enzyme-adapter-react-15": "^1.4.0",
     "enzyme-adapter-react-16": "^1.14.0",
     "moment": "^2.24.0",
-    "moment-timezone": "^0.5.25",
+    "moment-timezone": "^0.5.35",
     "react": "^16.8.6",
     "react-dom": "^16.8.6",
     "react-scripts": "3.0.1"
diff --git a/world_clocks/yarn.lock b/world_clocks/yarn.lock
index 0878280..2ba8738 100644
--- a/world_clocks/yarn.lock
+++ b/world_clocks/yarn.lock
@@ -6337,10 +6337,10 @@ mkdirp@0.5.1, mkdirp@0.5.x, mkdirp@^0.5.0, mkdirp@^0.5.1, mkdirp@~0.5.0, mkdirp@
   dependencies:
     minimist "0.0.8"
 
-moment-timezone@^0.5.25:
-  version "0.5.25"
-  resolved "https://registry.yarnpkg.com/moment-timezone/-/moment-timezone-0.5.25.tgz#a11bfa2f74e088327f2cd4c08b3e7bdf55957810"
-  integrity sha512-DgEaTyN/z0HFaVcVbSyVCUU6HeFdnNC3vE4c9cgu2dgMTvjBUBdBzWfasTBmAW45u5OIMeCJtU8yNjM22DHucw==
+moment-timezone@^0.5.35:
+  version "0.5.35"
+  resolved "https://registry.yarnpkg.com/moment-timezone/-/moment-timezone-0.5.35.tgz#6fa2631bdbe8ff04f6b8753f7199516be6dc9839"
+  integrity sha512-cY/pBOEXepQvlgli06ttCTKcIf8cD1nmNwOKQQAdHBqYApQSpAqotBMX0RJZNgMp6i0PlZuf1mFtnlyEkwyvFw==
   dependencies:
     moment ">= 2.9.0"