diff --git a/config/cesm/config_inputdata.xml b/config/cesm/config_inputdata.xml
index b61dcb5778a..2cb2d6781ba 100644
--- a/config/cesm/config_inputdata.xml
+++ b/config/cesm/config_inputdata.xml
@@ -40,6 +40,10 @@
     <comment> NEON Tower data for datm </comment>
     <protocol>wget</protocol>
     <address>https://s3.data.neonscience.org/neon-ncar/NEON/</address>
+    <!-- inventory is a CSV list of available data files and the valid date for each -->
+    <!-- expected format is pathtofile,YYYY-MM-DD HH:MM:SS -->
+    <!-- one per line where the date stamp indicates the last modification time of the file -->
+    <inventory>../listing.csv</inventory>
   </server>
 
 </inputdata>
diff --git a/config/xml_schemas/config_inputdata.xsd b/config/xml_schemas/config_inputdata.xsd
index 88bab745216..fee8e973c10 100644
--- a/config/xml_schemas/config_inputdata.xsd
+++ b/config/xml_schemas/config_inputdata.xsd
@@ -8,12 +8,16 @@
           </xs:annotation>
           <xs:complexType>
             <xs:sequence>
-	      <xs:element type="xs:string" name="comment" minOccurs="0"/>
+              <xs:element type="xs:string" name="comment" minOccurs="0"/>
               <xs:element type="xs:string" name="protocol"/>
               <xs:element type="xs:string" name="address"/>
               <xs:element type="xs:string" name="user" minOccurs="0"/>
               <xs:element type="xs:string" name="password" minOccurs="0"/>
               <xs:element type="xs:string" name="checksum" minOccurs="0"/>
+                  <!-- inventory is a CSV list of available data files and the valid date for each -->
+                  <!-- expected format is pathtofile,YYYY-MM-DD HH:MM:SS -->
+                  <!-- it is currently only used for NEON tower data -->
+              <xs:element type="xs:string" name="inventory" minOccurs="0"/>
               <xs:element type="xs:string" name="ic_filepath" minOccurs="0"/>
             </xs:sequence>
           </xs:complexType>
diff --git a/scripts/lib/CIME/XML/inputdata.py b/scripts/lib/CIME/XML/inputdata.py
index 626b0089302..f6c033bb169 100644
--- a/scripts/lib/CIME/XML/inputdata.py
+++ b/scripts/lib/CIME/XML/inputdata.py
@@ -32,6 +32,11 @@ def get_next_server(self, attributes=None):
         chksum_file = None
         ic_filepath = None
         servernodes = self.get_children("server", attributes=attributes)
+
+        # inventory is a CSV list of available data files and the valid date for each
+        # expected format is pathtofile,YYYY-MM-DD HH:MM:SS
+        # currently only used for NEON tower data
+        inventory = None
         if not attributes:
             servernodes = [x for x in servernodes if not self.attrib(x)]
 
@@ -52,6 +57,10 @@ def get_next_server(self, attributes=None):
             unode = self.get_optional_child("user", root = self._servernode)
             if unode:
                 user =  self.text(unode)
+            invnode = self.get_optional_child("inventory", root = self._servernode)
+            if invnode:
+                inventory = self.text(invnode)
+
             pnode = self.get_optional_child("password", root = self._servernode)
             if pnode:
                 passwd =  self.text(pnode)
@@ -62,4 +71,4 @@ def get_next_server(self, attributes=None):
             if icnode:
                 ic_filepath =  self.text(icnode)
 
-        return protocol, address, user, passwd, chksum_file, ic_filepath
+        return protocol, address, user, passwd, chksum_file, ic_filepath, inventory
diff --git a/scripts/lib/CIME/case/check_input_data.py b/scripts/lib/CIME/case/check_input_data.py
index 54a9276ed2c..32bfffbb91e 100644
--- a/scripts/lib/CIME/case/check_input_data.py
+++ b/scripts/lib/CIME/case/check_input_data.py
@@ -22,7 +22,7 @@ def _download_checksum_file(rundir):
     chksum_found = False
     # download and merge all available chksum files.
     while protocol is not None:
-        protocol, address, user, passwd, chksum_file,_ = inputdata.get_next_server()
+        protocol, address, user, passwd, chksum_file,_,_ = inputdata.get_next_server()
         if protocol not in vars(CIME.Servers):
             logger.info("Client protocol {} not enabled".format(protocol))
             continue
@@ -190,7 +190,7 @@ def _downloadfromserver(case, input_data_root, data_list_dir, attributes=None):
         input_data_root = case.get_value('DIN_LOC_ROOT')
 
     while not success and protocol is not None:
-        protocol, address, user, passwd, _, ic_filepath = inputdata.get_next_server(attributes=attributes)
+        protocol, address, user, passwd, _, ic_filepath, _ = inputdata.get_next_server(attributes=attributes)
         logger.info("Checking server {} with protocol {}".format(address, protocol))
         success = case.check_input_data(protocol=protocol, address=address, download=True,
                                         input_data_root=input_data_root,
@@ -352,9 +352,24 @@ def check_input_data(case, protocol="svn", address=None, input_data_root=None, d
                         # proceed
                         if not os.path.exists(full_path):
                             print("Model {} missing file {} = '{}'".format(model, description, full_path))
+                            # Data download path must be DIN_LOC_ROOT, DIN_LOC_IC or RUNDIR
+
+                            rundir = case.get_value("RUNDIR")
                             if download:
-                                logger.warning("    Cannot download file since it lives outside of the input_data_root '{}'".format(input_data_root))
-                            no_files_missing = False
+                                if full_path.startswith(rundir):
+                                    filepath = os.path.dirname(full_path)
+                                    if not os.path.exists(filepath):
+                                        logger.info("Creating directory {}".format(filepath))
+                                        os.makedirs(filepath)
+                                    tmppath = full_path[len(rundir)+1:]
+                                    success = _download_if_in_repo(server, os.path.join(rundir,"inputdata"),
+                                                                   tmppath[10:],
+                                                                   isdirectory=isdirectory, ic_filepath='/')
+                                    no_files_missing = success
+                                else:
+                                    logger.warning("    Cannot download file since it lives outside of the input_data_root '{}'".format(input_data_root))
+                            else:
+                                no_files_missing = False
                         else:
                             logger.debug("  Found input file: '{}'".format(full_path))
                     else:
diff --git a/scripts/lib/CIME/test_scheduler.py b/scripts/lib/CIME/test_scheduler.py
index 90d8e450c2e..25980853906 100644
--- a/scripts/lib/CIME/test_scheduler.py
+++ b/scripts/lib/CIME/test_scheduler.py
@@ -484,10 +484,15 @@ def _create_newcase_phase(self, test):
 
             testmods_dir = files.get_value("TESTS_MODS_DIR", {"component": component})
             test_mod_file = os.path.join(testmods_dir, component, modspath)
+            # if no testmod is found check if a usermod of the same name exists and
+            # use it if it does.
             if not os.path.exists(test_mod_file):
-                error = "Missing testmod file '{}'".format(test_mod_file)
-                self._log_output(test, error)
-                return False, error
+                usermods_dir = files.get_value("USER_MODS_DIR", {"component": component})
+                test_mod_file = os.path.join(usermods_dir, modspath)
+                if not os.path.exists(test_mod_file):
+                    error = "Missing testmod file '{}', checked {} and {}".format(modspath, testmods_dir, usermods_dir)
+                    self._log_output(test, error)
+                    return False, error
 
             create_newcase_cmd += " --user-mods-dir {}".format(test_mod_file)