add documentation about new config variable LOG_TO_TERMINAL_ONLY

docs/Users_Guide/glossary.rst

@@ -2287,7 +2287,15 @@ METplus Configuration Glossary
    LOG_METPLUS
      Path to the METplus log file. Control the timestamp appended to the
      filename with :term:`LOG_TIMESTAMP_TEMPLATE`.
-     Set this variable to an empty string to turn off all logging.
+     Set this variable to an empty string or set :term:`LOG_TO_TERMINAL_ONLY`
+     = True to turn off all file logging and write all logs to the screen.
+
+     | *Used by:*  All
+
+   LOG_TO_TERMINAL_ONLY
+     Set to True to skip writing any log files and instead send all log output
+     to the screen. Sets :term:`LOG_METPLUS` to an empty string if True.
+     Defaults to False.
 
      | *Used by:*  All
 

docs/Users_Guide/systemconfiguration.rst

@@ -340,6 +340,19 @@ to the METplus log file::
 If set to false/no, the output is written to a separate
 file in the log directory named after the application.
 
+
+.. _log_to_terminal_only:
+
+LOG_TO_TERMINAL_ONLY
+""""""""""""""""""""
+
+If set to True, all log output is written to the screen only.
+This includes output from commands that are run, e.g. MET commands.
+No log files will be created and :ref:`log_metplus` will be set to an empty
+string. ::
+
+    LOG_TO_TERMINAL_ONLY = True
+
 Log Level Information
 ^^^^^^^^^^^^^^^^^^^^^