diff --git a/superset-frontend/src/explore/components/controls/AnnotationLayerControl/AnnotationLayer.jsx b/superset-frontend/src/explore/components/controls/AnnotationLayerControl/AnnotationLayer.jsx
index bc95bc487ee3..c444e027d9b2 100644
--- a/superset-frontend/src/explore/components/controls/AnnotationLayerControl/AnnotationLayer.jsx
+++ b/superset-frontend/src/explore/components/controls/AnnotationLayerControl/AnnotationLayer.jsx
@@ -334,7 +334,7 @@ class AnnotationLayer extends React.PureComponent {
                     ...x,
                     data: {
                       ...x.data,
-                      groupby: x.data.groupby.map(column =>
+                      groupby: x.data.groupby?.map(column =>
                         getColumnLabel(column),
                       ),
                     },
diff --git a/superset/db_engine_specs/snowflake.py b/superset/db_engine_specs/snowflake.py
index 578ded965bed..cd083a76b215 100644
--- a/superset/db_engine_specs/snowflake.py
+++ b/superset/db_engine_specs/snowflake.py
@@ -162,7 +162,7 @@ def convert_dttm(
             return f"TO_DATE('{dttm.date().isoformat()}')"
         if tt == utils.TemporalType.DATETIME:
             return f"""CAST('{dttm.isoformat(timespec="microseconds")}' AS DATETIME)"""
-        if tt == utils.TemporalType.TIMESTAMP:
+        if utils.TemporalType.TIMESTAMP in tt:
             return f"""TO_TIMESTAMP('{dttm.isoformat(timespec="microseconds")}')"""
         return None
 
diff --git a/tests/unit_tests/db_engine_specs/test_snowflake.py b/tests/unit_tests/db_engine_specs/test_snowflake.py
index 854d3f5f61c0..2f1171c33c3d 100644
--- a/tests/unit_tests/db_engine_specs/test_snowflake.py
+++ b/tests/unit_tests/db_engine_specs/test_snowflake.py
@@ -34,6 +34,7 @@
         ("DATE", "TO_DATE('2019-01-02')"),
         ("DATETIME", "CAST('2019-01-02T03:04:05.678900' AS DATETIME)"),
         ("TIMESTAMP", "TO_TIMESTAMP('2019-01-02T03:04:05.678900')"),
+        ("TIMESTAMP_NTZ", "TO_TIMESTAMP('2019-01-02T03:04:05.678900')"),
     ],
 )
 def test_convert_dttm(actual: str, expected: str, dttm: datetime) -> None: