diff --git a/doc/sphinx/source/input.rst b/doc/sphinx/source/input.rst
index d1aa66fcd6..a6cbfa0e58 100644
--- a/doc/sphinx/source/input.rst
+++ b/doc/sphinx/source/input.rst
@@ -222,6 +222,8 @@ A list of the datasets for which a cmorizers is available is provided in the fol
 +------------------------------+------------------------------------------------------------------------------------------------------+------+-----------------+
 | ESACCI-SST                   | ts, tsStderr (Amon)                                                                                  |   2  | NCL             |
 +------------------------------+------------------------------------------------------------------------------------------------------+------+-----------------+
+| ESACCI-WATERVAPOUR           | prw (Amon)                                                                                           |   3  | Python          |
++------------------------------+------------------------------------------------------------------------------------------------------+------+-----------------+
 | ESRL                         | co2s (Amon)                                                                                          |   2  | NCL             |
 +------------------------------+------------------------------------------------------------------------------------------------------+------+-----------------+
 | FLUXCOM                      | gpp (Lmon)                                                                                           |   3  | Python          |
diff --git a/esmvaltool/cmorizers/obs/cmor_config/ESACCI-WATERVAPOUR.yml b/esmvaltool/cmorizers/obs/cmor_config/ESACCI-WATERVAPOUR.yml
new file mode 100644
index 0000000000..400fb7e8da
--- /dev/null
+++ b/esmvaltool/cmorizers/obs/cmor_config/ESACCI-WATERVAPOUR.yml
@@ -0,0 +1,34 @@
+---
+# Common global attributes for Cmorizer output
+
+
+# Input
+# CDR-2
+filename: 'ESACCI-WATERVAPOUR-L3S-TCWV-*-05deg-{year}{month}-fv3.1.nc'
+# CDR-1
+# filename: 'dataset3_1/CDR-1/monthlies/ESACCI-WATERVAPOUR-L3?-TCWV-*-05deg-{year}{month}-fv3.1.nc'
+attributes:
+  dataset_id: ESACCI-WATERVAPOUR
+  # CDR-2
+  version: 'CDR2-L3S-05deg_fv3.1'
+  # CDR-1
+  # version: 'CDR1-L3-05deg_fv3.1'
+  tier: 3
+  modeling_realm: sat
+  project_id: OBS
+  source: "ftp.brockmann-consult.de, access currently restricted"
+  reference: ["esacci-watervapour"]
+  comment: "Preliminary data."
+
+# Variables to cmorize (here use only filename prefix)
+variables:
+  prw:
+    mip: Amon
+    raw: tcwv
+    # Output automatially added: Amon_<var>_200910-200910.nc
+    # CDR-2
+    file: OBS_ESACCI-WATERVAPOUR-CDR2-L3S-TCWV-05deg
+    # CDR-1
+    # file: OBS_ESACCI-WATERVAPOUR-CDR1-L3-TCWV-05deg
+    start_year: 2003
+    end_year: 2017
diff --git a/esmvaltool/cmorizers/obs/cmorize_obs_esacci_watervapour.py b/esmvaltool/cmorizers/obs/cmorize_obs_esacci_watervapour.py
new file mode 100644
index 0000000000..a3852f6885
--- /dev/null
+++ b/esmvaltool/cmorizers/obs/cmorize_obs_esacci_watervapour.py
@@ -0,0 +1,84 @@
+"""ESMValTool CMORizer for ESACCI-WATERVAPOUR data.
+
+Tier
+   Tier 3: currently still restricted because preliminary.
+
+Source
+   Marc Schröder, ftp.brockmann-consult.de
+
+Last access
+   20210329
+
+Download and processing instructions
+   FTP server: ftp.brockmann-consult.de, access currently restricted
+               data/tcwv/dataset3_1/CDR-*/...
+   All files need to be in one directory, not in yearly subdirectories.
+
+Modification history
+   20210607-weigel_katja: Fix for monthly time bounds.
+   20210408-weigel_katja: written.
+
+"""
+
+import logging
+import os
+
+import iris
+
+from esmvalcore.preprocessor import concatenate
+from esmvalcore.cmor.check import _get_time_bounds
+from esmvaltool.cmorizers.obs.utilities import (convert_timeunits, fix_coords,
+                                                fix_var_metadata,
+                                                save_variable, set_global_atts)
+
+logger = logging.getLogger(__name__)
+
+
+def extract_variable(var_info, raw_info, attrs, year):
+    """Extract to all vars."""
+    cubes = iris.load(raw_info['file'])
+    rawvar = raw_info['name']
+
+    for cube in cubes:
+        if cube.var_name == rawvar:
+            fix_var_metadata(cube, var_info)
+            convert_timeunits(cube, year)
+            fix_coords(cube, overwrite_time_bounds=False)
+            set_global_atts(cube, attrs)
+            # Remove disfunctional ancillary data without sandard name
+            for ancillary_variable_, dim in cube._ancillary_variables_and_dims:
+                cube.remove_ancillary_variable(ancillary_variable_)
+            return cube
+
+
+def cmorization(in_dir, out_dir, cfg, _):
+    """Cmorize data."""
+    # cmor_table = cfg['cmor_table']
+    glob_attrs = cfg['attributes']
+
+    # run the cmorization
+    for var, vals in cfg['variables'].items():
+        var_info = cfg['cmor_table'].get_variable(vals['mip'], var)
+        glob_attrs['mip'] = vals['mip']
+        raw_info = {'name': vals['raw'], 'file': vals['file']}
+        inpfile = os.path.join(in_dir, cfg['filename'])
+        logger.info("CMORizing var %s from file type %s", var, inpfile)
+        # years = range(vals['start_year'], vals['end_year'] + 1)
+        months = ["0" + str(mo) for mo in range(1, 10)] + ["10", "11", "12"]
+        for year in range(vals['start_year'], vals['end_year'] + 1):
+            monthly_cubes = []
+            for month in months:
+                raw_info['file'] = inpfile.format(year=year, month=month)
+                logger.info("CMORizing var %s from file type %s", var,
+                            raw_info['file'])
+                monthly_cubes.append(extract_variable(var_info, raw_info,
+                                                      glob_attrs, year))
+            yearly_cube = concatenate(monthly_cubes)
+            # Fix monthly time bounds
+            time = yearly_cube.coord('time')
+            time.bounds = _get_time_bounds(time, 'mon')
+            save_variable(yearly_cube,
+                          var,
+                          out_dir,
+                          glob_attrs,
+                          unlimited_dimensions=['time'])
diff --git a/esmvaltool/recipes/examples/recipe_check_obs.yml b/esmvaltool/recipes/examples/recipe_check_obs.yml
index adedde1fa1..45e08dc2f4 100644
--- a/esmvaltool/recipes/examples/recipe_check_obs.yml
+++ b/esmvaltool/recipes/examples/recipe_check_obs.yml
@@ -1117,6 +1117,17 @@ diagnostics:
     scripts: null
 
 
+  ESACCI-WATERVAPOUR:
+    description: ESACCI-WV check
+    variables:
+      prw:
+    additional_datasets:
+      - {dataset: ESACCI-WATERVAPOUR, project: OBS, mip: Amon, tier: 3,
+         type: sat, version: CDR2-L3S-05deg_fv3.1,
+         start_year: 2003, end_year: 2017}
+    scripts: null
+
+
   GRACE:
     description: GRACE check
     variables:
diff --git a/esmvaltool/references/esacci-watervapour.bibtex b/esmvaltool/references/esacci-watervapour.bibtex
new file mode 100644
index 0000000000..bdccb12a5e
--- /dev/null
+++ b/esmvaltool/references/esacci-watervapour.bibtex
@@ -0,0 +1,10 @@
+@misc{esacci-watervapour,
+      doi = {CCIWV.REP.015},
+      url = {https://climate.esa.int/documents/357/Water_Vapour_cci_D4.2_CRDP_v2.1.pdf},
+      year = 2020,
+      month = {october},
+      publisher = {ESA / ECSAT},
+      issue = {2.1},
+      author = {Michaela Hegglin, Olaf Danne, Marc Schröder, Hao Ye},
+      title = {Climate Research Data Package (CRDP) Water Vapour Climate Change Initiative (WV{\_}cci)- CCI+ Phase 1}
+}