diff --git a/README.md b/README.md
index 29f92fa..e3db422 100644
--- a/README.md
+++ b/README.md
@@ -26,5 +26,5 @@ for example, using `pass` password:
 
 ```sh
 $ pip install -r requirements.txt
-$ TD_USERPASS=pass FLASK_APP=src/app flask run
+$ TD_USERPASS=pass TZ=UTC FLASK_APP=src/app flask run
 ```