diff --git a/alcf/__init__.py b/alcf/__init__.py
index dfdb9f3..2f33f53 100644
--- a/alcf/__init__.py
+++ b/alcf/__init__.py
@@ -1,4 +1,4 @@
-__version__ = '1.8.1'
+__version__ = '1.9.0'
 
 META = {
 	'software': 'ALCF (https://alcf.peterkuma.net)',
diff --git a/docs/installation/index.md b/docs/installation/index.md
index 996510f..9c2e70a 100644
--- a/docs/installation/index.md
+++ b/docs/installation/index.md
@@ -196,6 +196,21 @@ the [Semantic Versioning](https://semver.org). Installation instructions
 have been changing with versions. Please follow the installation instructions
 in the documentation of the particular version.
 
+#### [1.9.0](https://github.com/alcf-lidar/alcf/releases/tag/v1.9.0) (2024-05-03)
+
+<details>
+<summary>Release notes</summary>
+<ul>
+<li>Improvements in logging and error reporting.</li>
+<li>Added --version option to print version and exit.</li>
+<li>Added generic output file attributes (version and software).</li>
+<li>alcf model: Empty files are no longer output.</li>
+<li>alcf model: Check for filename instead of time variable in the UM module to ignore the orography file.</li>
+<li>alcf stats: Avoid division by zero.</li>
+<li>Improvements in the documentation.</li>
+</ul>
+</details>
+
 #### [1.8.1](https://github.com/alcf-lidar/alcf/releases/tag/v1.8.1) (2024-04-26)
 
 <details>
diff --git a/setup.py b/setup.py
index 6e63ca3..8fd0b3d 100755
--- a/setup.py
+++ b/setup.py
@@ -20,7 +20,7 @@ def run(self):
 
 setup(
 	name='alcf',
-	version='1.8.1',
+	version='1.9.0',
 	description='Automatic Lidar and Ceilometer Framework (ALCF)',
 	author='Peter Kuma, Adrian J. McDonald, Olaf Morgenstern, Richard Querel, Israel Silber, Connor J. Flynn',
 	author_email='peter@peterkuma.net',