def new_nc_file(suffix='', directory=settings.BASE_DATA_DIR, metadata=None):
    if suffix and not suffix.startswith('_'):
        suffix = '_' + suffix
    if metadata is None:
        metadata = all_metadata()
    root_path = os.path.join(directory, time.strftime('%Y-%m-%d_%H%M%S') + suffix + nc.NCFile.EXTENSION)
    logger.debug("Creating new NCFile with path %s" % root_path)
    return nc.NCFile(root_path, metadata=metadata)