NCAR · hkershaw-brown · Aug 13, 2025 · Jul 17, 2025 · Jul 18, 2025 · Jul 22, 2025
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
@@ -22,6 +22,13 @@ individual files.
 
 The changes are now listed with the most recent at the top.
 
+**August 13 2025 :: IODA2obsq. Tag v11.13.0**
+
+- Initial pyjedi package for DART JEDI interoperability.
+- ioda2obsq tool for conventional observations.  
+
+*contributed by Stephen Herbener, DART collaboration with JCSDA*
+
 **July 30 2025 :: MOM6 interpolation bug-fixes. Tag v11.12.1**
 
 - Fixes quad points assignment in model_interpolate

diff --git a/conf.py b/conf.py
@@ -21,7 +21,7 @@
 author = 'Data Assimilation Research Section'
 
 # The full version, including alpha/beta/rc tags
-release = '11.12.1'
+release = '11.13.0'
 root_doc = 'index'
 
 # -- General configuration ---------------------------------------------------

diff --git a/guide/pytools.rst b/guide/pytools.rst
@@ -4,28 +4,92 @@
 DART Python tools
 =========================
 
+Installation
+------------
+
 DART provides a set of Python tools that can be used to work with DART data and models.
 These tools are located in the DART/pytools directory.
 
 We recommend creating a `virtual environment <https://docs.python.org/3/library/venv.html>`__ 
 to install DART Python tools. This helps to keep the DART Python tools and their dependencies 
 isolated from other Python packages you may have installed.
 
-.. code-block:: text
+.. code-block:: bash
 
     python3 -m venv py-dart
     source py-dart/bin/activate
 
 You can then install the DART Python tools by navigating to the DART/pytools directory and running:
 
-.. code-block:: text
+.. code-block:: bash
 
     cd DART/pytools
     pip install -r pyDART.txt
 
 
 When you want to use the DART Python tools in a new session you will need to activate the virtual environment:
 
+.. code-block:: bash
+
+    source py-dart/bin/activate
+
+To deactivate the virtual environment when you are done, simply run:
+
 .. code-block:: text
 
-    source py-dart/bin/activate
+    deactivate
+
+Available Tool Packages
+-----------------------
+
+pyjedi
+^^^^^^
+
+The `pyjedi` package provides utilities for DART JEDI interoperability.
+This is a new package that is under development and is not fully functional yet.
+At this time, a new converter is available that can transform a JEDI IODA observation file into a DART observation sequence file.
+This converter can be run as follows:
+
+.. code-block:: bash
+
+    ioda2obsq <yamlConfigFile> <inputIodaFile> <outputObsqFile>
+
+where ``<yamlConfigFile>`` is a YAML configuration file that specifies the mapping between JEDI IODA observation
+variables and DART observation variables, ``<inputIodaFile>`` is the input JEDI IODA observation file,
+and ``<outputObsqFile>`` is the output DART observation sequence file.
+
+The YAML configuration file contains the mapping between JEDI IODA observation variables and DART observation types along
+with the specification of the desired vertical coordinate variable.
+Here is an example configuration file for radiosondes:
+
+.. code-block:: yaml
+
+    ---
+
+    ioda to obsq converter:
+      observation variables:
+        - name: airTemperature
+          type: RADIOSONDE_TEMPERATURE
+        - name: specificHumidity
+          type: RADIOSONDE_SPECIFIC_HUMIDITY
+        - name: windEastward
+          type: RADIOSONDE_U_WIND_COMPONENT
+        - name: windNorthward
+          type: RADIOSONDE_V_WIND_COMPONENT
+
+      vertical coordinate:
+        name: MetaData/pressure
+        units: "pressure (Pa)"
+
+The `name:` entries are the names of the variables in the JEDI IODA observation file, and the `type:` entries
+are the corresponding DART observation types.
+The `vertical coordinate` section specifies the variable that will be used as the vertical coordinate in
+the DART observation sequence file.
+Note that in the `vertical coordinate` section, the `name:` entry must specify the full netcdf path to the variabile
+in the JEDI IODA observation file, and the `units:` entry specifies the units to be used in the DART observation sequence file.
+
+.. note::
+
+    The `ioda2obsq` tool is under active development and has limited functionality at this time.
+    It is expected that more features will be added soon, including support for satellite radiance observation types.
+    In its current state, it is primarily intended for use with radiosonde and similar conventional observation types.
diff --git a/pytools/pyDART.txt b/pytools/pyDART.txt
@@ -1 +1,2 @@
 -e ./pyqceff
+-e ./pyjedi
diff --git a/pytools/pyjedi/README.md b/pytools/pyjedi/README.md
@@ -0,0 +1,52 @@
+# pyjedi
+
+Python package for JEDI utilities.
+
+## Installation
+
+To install `pyjedi` in editable/development mode using pip:
+
+   ```sh
+   pip install -e DART/pytools/pyjedi
+   ```
+
+where DART is the path to DART.
+
+> **Note:** If you update DART with `git pull`, using the editable install (`pip install -e DART/pytools/pyjedi`) ensures your installed package always matches the latest source code.
+
+
+## Usage
+
+After installation, you can use the `ioda2obsq` script to convert a IODA observation file into a DART obs_seq.out file:
+
+```sh
+ioda2obsq yamlConfigFile inputIodaFile outputObsqFile
+```
+
+To view the help
+```sh
+ioda2obsq -h
+```
+
+The yamConfigFile is used to tell ioda2obsq which variables, and their type, from the input IODA file to convert, as well as define the vertical coordinate.
+Here is a sample from the radiosonde test case:
+```yaml
+---
+
+ioda to obsq converter:
+  observation variables:
+    - name: airTemperature
+      type: RADIOSONDE_TEMPERATURE
+    - name: specificHumidity
+      type: RADIOSONDE_SPECIFIC_HUMIDITY
+    - name: windEastward
+      type: RADIOSONDE_U_WIND_COMPONENT
+    - name: windNorthward
+      type: RADIOSONDE_V_WIND_COMPONENT
+
+  vertical coordinate:
+    name: MetaData/height
+    units: "height (m)"
+```
+
+Note "observation variables" is the list of variables you intend to assimilate in the DA job.
diff --git a/pytools/pyjedi/pyproject.toml b/pytools/pyjedi/pyproject.toml
@@ -0,0 +1,33 @@
+[build-system]
+requires = ["setuptools>=61.0"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "pyjedi"
+version = "0.1.0"
+description = "Python package for JEDI utilities."
+authors = [
+    { name = "DART", email = "[email protected]" }
+]
+readme = "README.md"
+requires-python = ">=3.8"
+license = { text = "Apache-2.0" }
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: Apache Software License",
+    "Operating System :: OS Independent",
+]
+dependencies = [
+    "numpy",
+    "pandas>=2.2.0",
+    "PyYAML",
+    "netCDF4",
+    "pydartdiags>=0.6.1",
+]
+
+[project.scripts]
+ioda2obsq = "pyjedi.ioda2obsq:main"
+
+[project.urls]
+Homepage = "https://github.com/NCAR/DART"
+Repository = "https://github.com/NCAR/DART"
diff --git a/pytools/pyjedi/src/pyjedi/__init__.py b/pytools/pyjedi/src/pyjedi/__init__.py