diff --git a/index.js b/index.js
index f639903a..1b52ab83 100644
--- a/index.js
+++ b/index.js
@@ -1,11 +1,11 @@
 "use strict";
-const fs   = require("fs"),
-      path = require("path");
+const fs = require("fs");
+const path = require("path");
 
-fs.readdirSync(path.join(__dirname, "lib/lang")).forEach(pathname => {
+for(const pathname of fs.readdirSync(path.join(__dirname, "lib/lang"))) {
   const match = /^([^\.].*)\.js$/.exec(pathname);
 
   if(match) {
     exports[match[1]] = require("./lib/lang/" + pathname);
   }
-});
+}
diff --git a/lib/lang/zh-tw.js b/lib/lang/zh-tw.js
index 84463c55..d76db89c 100644
--- a/lib/lang/zh-tw.js
+++ b/lib/lang/zh-tw.js
@@ -27,6 +27,8 @@ module.exports = require("../template")({
   "light-snow": "小雪",
   "medium-snow": "降雪",
   "heavy-snow": "鵝毛大雪",
+  "possible-thunderstorm": "可能有雷暴",
+  "thunderstorm": "雷暴",
   "light-wind": "微風",
   "medium-wind": "有風",
   "heavy-wind": "推人大風",
@@ -61,6 +63,13 @@ module.exports = require("../template")({
   "thursday": "周四",
   "friday": "周五",
   "saturday": "周六",
+  "next-sunday": "下周日",
+  "next-monday": "下周一",
+  "next-tuesday": "下周二",
+  "next-wednesday": "下周三",
+  "next-thursday": "下周四",
+  "next-friday": "下周五",
+  "next-saturday": "下周六",
   "minutes": "$1分鐘",
   "fahrenheit": "$1\u00B0F",
   "celsius": "$1\u00B0C",
diff --git a/package.json b/package.json
index 41d8372d..06963b54 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "forecast-io-translations",
-  "version": "1.41.5",
+  "version": "1.42.0",
   "description": "translate the Dark Sky API into any language",
   "author": {
     "name": "The Dark Sky Company",
diff --git a/test_cases/zh-tw.json b/test_cases/zh-tw.json
index b4e35f7e..69fcf5c9 100644
--- a/test_cases/zh-tw.json
+++ b/test_cases/zh-tw.json
@@ -98,6 +98,11 @@
   "潮濕，局部多雲":
     ["title", ["and", "high-humidity", "light-clouds"]],
 
+  "多雲，可能有雷暴":
+    ["title", ["and", "medium-clouds", "possible-thunderstorm"]],
+
+  "多雲，雷暴":
+    ["title", ["and", "medium-clouds", "thunderstorm"]],
 
   "在接下來一個小時內晴朗。":
     ["sentence", ["for-hour", "clear"]],
@@ -135,6 +140,9 @@
   "大量降水將持續至下午。":
     ["sentence", ["until", "heavy-precipitation", "afternoon"]],
 
+  "雷暴將持續至下周一。":
+  ["sentence", ["until", "thunderstorm", "next-monday"]],
+
   "微風持續至下午。":
     ["sentence", ["during", "light-wind", "afternoon"]],