diff --git a/tests/window/test_tumbling.py b/tests/window/test_tumbling.py
index 9fe41a4..361e0f1 100644
--- a/tests/window/test_tumbling.py
+++ b/tests/window/test_tumbling.py
@@ -45,6 +45,7 @@ def test_no_closed_results(self):
 
     def test_closed_results_found(self):
         conn = duckdb.connect()
+        conn.execute("SET timezone = 'UTC'")
 
         conn.sql('''
         CREATE TABLE test_table (