diff --git a/modules/aeolus/datasource.py b/modules/aeolus/datasource.py
index 678f87bb3f183ae3ae9bf0db0d4be37492091e6f..e3d9c743051a4b3dc4f91a4c3411e8eec7a4926b 100644
--- a/modules/aeolus/datasource.py
+++ b/modules/aeolus/datasource.py
@@ -9,7 +9,6 @@ from util.util import GenericException
 
 class Files:
     def __init__(self, files_path, file_time_span, pattern):
-        #self.flist = glob.glob(files_path + 'raob_soundings*.nc')
         self.flist = glob.glob(files_path + pattern)
         if len(self.flist) == 0:
             raise GenericException('no matching files found in: ' + files_path)
@@ -55,6 +54,17 @@ class Files:
             return None, None, None
 
 
+class GFSfiles(Files):
+    def __init__(self, files_path, file_time_span, pattern):
+        super().__init__(files_path, file_time_span, pattern)
+
+    def get_datetime(self, pathname):
+        filename = os.path.split(pathname)[1]
+        dto = datetime.datetime.strptime(filename, 'gfs.%y%m%d%H_F012.h5').replace(tzinfo=timezone.utc)
+        dto += datetime.timedelta(hours=12)
+        return dto
+
+
 class AMVFiles:
 
     def __init__(self, files_path, file_time_span, pattern, band='14', elem_name=None, line_name=None, lat_name=None,