diff --git a/docs/Users_Guide/glossary.rst b/docs/Users_Guide/glossary.rst
index 8dce91f7b..3a6eb5806 100644
--- a/docs/Users_Guide/glossary.rst
+++ b/docs/Users_Guide/glossary.rst
@@ -10423,7 +10423,10 @@ METplus Configuration Glossary
      | *Used by:* TCDiag
 
    TC_DIAG_OUTPUT_PREFIX
-     Specify the value for 'output_prefix' in the MET configuration file for TCDiag.
+     .. warning:: **DEPRECATED:** Please use :term:`TC_DIAG_OUTPUT_BASE_FORMAT` instead.
+
+   TC_DIAG_OUTPUT_BASE_FORMAT
+     Specify the value for 'output_base_format' in the MET configuration file for TCDiag.
 
      | *Used by:* TCDiag
 
diff --git a/docs/Users_Guide/wrappers.rst b/docs/Users_Guide/wrappers.rst
index 112e8d93c..f05daccd7 100644
--- a/docs/Users_Guide/wrappers.rst
+++ b/docs/Users_Guide/wrappers.rst
@@ -8250,7 +8250,7 @@ METplus Configuration
 | :term:`TC_DIAG_NC_CYL_GRID_FLAG`
 | :term:`TC_DIAG_NC_DIAG_FLAG`
 | :term:`TC_DIAG_CIRA_DIAG_FLAG`
-| :term:`TC_DIAG_OUTPUT_PREFIX`
+| :term:`TC_DIAG_OUTPUT_BASE_FORMAT`
 | :term:`TC_DIAG_SKIP_IF_OUTPUT_EXISTS`
 | :term:`TC_DIAG_MET_CONFIG_OVERRIDES`
 | :term:`TC_DIAG_SKIP_VALID_TIMES`
@@ -8715,8 +8715,8 @@ ${METPLUS_OUTPUT_PREFIX}
 
    * - METplus Config(s)
      - MET Config File
-   * - :term:`TC_DIAG_OUTPUT_PREFIX`
-     - output_prefix
+   * - :term:`TC_DIAG_OUTPUT_BASE_FORMAT`
+     - output_base_format
 
 ${METPLUS_MET_CONFIG_OVERRIDES}
 """""""""""""""""""""""""""""""
diff --git a/internal/tests/pytests/wrappers/tc_diag/test_tc_diag_wrapper.py b/internal/tests/pytests/wrappers/tc_diag/test_tc_diag_wrapper.py
index 626b0fab4..4b0ed0f54 100644
--- a/internal/tests/pytests/wrappers/tc_diag/test_tc_diag_wrapper.py
+++ b/internal/tests/pytests/wrappers/tc_diag/test_tc_diag_wrapper.py
@@ -203,7 +203,7 @@ def set_minimum_config_settings(config):
 
         ({'TC_DIAG_CIRA_DIAG_FLAG': 'True', }, {'METPLUS_CIRA_DIAG_FLAG': 'cira_diag_flag = TRUE;'}),
 
-        ({'TC_DIAG_OUTPUT_PREFIX': 'my_prefix', }, {'METPLUS_OUTPUT_PREFIX': 'output_prefix = "my_prefix";'}),
+        ({'TC_DIAG_OUTPUT_BASE_FORMAT': 's{storm_id}_{technique}_doper_{init_ymdh}', }, {'METPLUS_OUTPUT_BASE_FORMAT': 'output_base_format = "s{storm_id}_{technique}_doper_{init_ymdh}";'}),
         ({'TC_DIAG_ONE_TIME_PER_FILE_FLAG': 'false', },
          {'METPLUS_ONE_TIME_PER_FILE_FLAG': 'one_time_per_file_flag = FALSE;'}),
     ]
diff --git a/metplus/wrappers/tc_diag_wrapper.py b/metplus/wrappers/tc_diag_wrapper.py
index 5e715efa3..a940c3a5d 100755
--- a/metplus/wrappers/tc_diag_wrapper.py
+++ b/metplus/wrappers/tc_diag_wrapper.py
@@ -63,13 +63,14 @@ class TCDiagWrapper(RuntimeFreqWrapper):
         'METPLUS_NC_DIAG_FLAG',
         'METPLUS_NC_CYL_GRID_FLAG',
         'METPLUS_CIRA_DIAG_FLAG',
-        'METPLUS_OUTPUT_PREFIX',
+        'METPLUS_OUTPUT_BASE_FORMAT',
         'METPLUS_ONE_TIME_PER_FILE_FLAG',
     ]
 
     # deprecated env vars that are no longer supported in the wrapped MET conf
     DEPRECATED_WRAPPER_ENV_VAR_KEYS = [
         'OUTPUT_PREFIX',
+        'METPLUS_OUTPUT_PREFIX',
     ]
 
     def __init__(self, config, instance=None):
@@ -232,7 +233,7 @@ def create_c_dict(self):
         self.add_met_config(name='nc_diag_flag', data_type='bool')
         self.add_met_config(name='cira_diag_flag', data_type='bool')
 
-        self.add_met_config(name='output_prefix', data_type='string')
+        self.add_met_config(name='output_base_format', data_type='string')
 
         return c_dict
 
diff --git a/parm/met_config/TCDiagConfig_wrapped b/parm/met_config/TCDiagConfig_wrapped
index 9c2bfa599..3a9f63b79 100644
--- a/parm/met_config/TCDiagConfig_wrapped
+++ b/parm/met_config/TCDiagConfig_wrapped
@@ -182,8 +182,8 @@ ${METPLUS_CIRA_DIAG_FLAG}
 
 tmp_dir = "${MET_TMP_DIR}";
 
-//output_prefix =
-${METPLUS_OUTPUT_PREFIX}
+//output_base_format =
+${METPLUS_OUTPUT_BASE_FORMAT}
 
 //version       = "V11.1.0";
 
diff --git a/parm/use_cases/met_tool_wrapper/TCDiag/TCDiag.conf b/parm/use_cases/met_tool_wrapper/TCDiag/TCDiag.conf
index 390535d8a..6a094caf1 100644
--- a/parm/use_cases/met_tool_wrapper/TCDiag/TCDiag.conf
+++ b/parm/use_cases/met_tool_wrapper/TCDiag/TCDiag.conf
@@ -131,6 +131,6 @@ TC_DIAG_DOMAIN_INFO2_DELTA_RANGE_KM = 2.0
 #TC_DIAG_NC_CYL_GRID_FLAG =
 #TC_DIAG_NC_DIAG_FLAG =
 #TC_DIAG_CIRA_DIAG_FLAG =
-#TC_DIAG_OUTPUT_PREFIX =
+#TC_DIAG_OUTPUT_BASE_FORMAT =
 
 #LOG_LEVEL=DEBUG
\ No newline at end of file