diff --git a/core/modules/datetime/src/Tests/Views/FilterDateTimeTest.php b/core/modules/datetime/src/Tests/Views/FilterDateTimeTest.php
index 02b12b3..068c88e 100644
--- a/core/modules/datetime/src/Tests/Views/FilterDateTimeTest.php
+++ b/core/modules/datetime/src/Tests/Views/FilterDateTimeTest.php
@@ -40,6 +40,9 @@ public function setUp() {
 
     static::$date = REQUEST_TIME + 86400;
 
+    // Set the timezone.
+    date_default_timezone_set(static::$timezone);
+
     // Add some basic test nodes.
     $dates = array(
       '2000-10-10',