diff --git a/src/sirocco/core/_tasks/icon_task.py b/src/sirocco/core/_tasks/icon_task.py
index 8b564e5..c643da3 100644
--- a/src/sirocco/core/_tasks/icon_task.py
+++ b/src/sirocco/core/_tasks/icon_task.py
@@ -13,16 +13,17 @@
 class IconTask(ConfigIconTaskSpecs, Task):
     core_namelists: dict[str, f90nml.Namelist] = field(default_factory=dict)
 
-    def init_namelists(self):
+    def init_core_namelists(self):
         """Read in or create namelists"""
         self.core_namelists = {}
         for name, cfg_nml in self.namelists.items():
             if (nml_path := self.config_root / cfg_nml.path).exists():
                 self.core_namelists[name] = f90nml.read(nml_path)
             else:
+                # If namelist does not exist, build it from the users given specs
                 self.core_namelists[name] = f90nml.Namelist()
 
-    def update_nml_from_config(self):
+    def update_core_namelists_from_config(self):
         """Update namelists from user input"""
 
         # TODO: implement format for users to reference parameters and date in their specs
@@ -31,9 +32,9 @@ def update_nml_from_config(self):
             for section, params in cfg_nml.specs.items():
                 section_name, k = self.section_index(section)
                 # Create section if non existant
-                # NOTE: f90nml will automatially create the corresponding nested f90nml.Namelist
-                #       objects, no need to explicitly use the f90nml.Namelist class constructor
                 if section_name not in core_nml:
+                    # NOTE: f90nml will automatially create the corresponding nested f90nml.Namelist
+                    #       objects, no need to explicitly use the f90nml.Namelist class constructor
                     core_nml[section_name] = {} if k is None else [{}]
                 # Update namelist with user input
                 # NOTE: unlike FORTRAN convention, user index starts at 0 as in Python
@@ -42,14 +43,30 @@ def update_nml_from_config(self):
                 nml_section = core_nml[section_name] if k is None else core_nml[section_name][k]
                 nml_section.update(params)
 
-    def update_nml_from_workflow(self):
+    def update_core_namelists_from_workflow(self):
         self.core_namelists["icon_master.namelist"]["master_time_control_nml"].update(
-            {"experimentStartDate": self.start_date, "experimentStopDate": self.end_date}
+            {
+                "experimentStartDate": self.start_date.isoformat() + "Z",
+                "experimentStopDate": self.end_date.isoformat() + "Z",
+            }
         )
         self.core_namelists["icon_master.namelist"]["master_nml"]["lrestart"] = any(
             in_data.type == "icon_restart" for in_data in self.inputs
         )
 
+    def dump_core_namelists(self):
+        for name, cfg_nml in self.namelists.items():
+            nml_path = self.config_root / cfg_nml.path
+            suffix = ("_".join([str(p) for p in self.coordinates.values()])).replace(" ", "_")
+            dump_path = nml_path.parent / (nml_path.name + "_" + suffix)
+            self.core_namelists[name].write(dump_path)
+
+    def create_workflow_namelists(self):
+        self.init_core_namelists()
+        self.update_core_namelists_from_config()
+        self.update_core_namelists_from_workflow()
+        self.dump_core_namelists()
+
     @staticmethod
     def section_index(section_name):
         multi_section_pattern = re.compile(r"(.*)\[([0-9]+)\]$")