diff --git a/.github/workflows/ci_tests.yaml b/.github/workflows/ci_tests.yaml
index 6e00ac5cc90..bb66d52800d 100644
--- a/.github/workflows/ci_tests.yaml
+++ b/.github/workflows/ci_tests.yaml
@@ -93,7 +93,7 @@ jobs:
                         pandas xarray netCDF4 packaging \
                         ${{ matrix.optional-packages }} \
                         build dvc make pytest>=6.0 \
-                        pytest-cov pytest-doctestplus pytest-mpl sphinx-gallery tomli
+                        pytest-cov pytest-doctestplus pytest-mpl sphinx-gallery
 
       # Show installed pkg information for postmortem diagnostic
       - name: List installed packages
diff --git a/.github/workflows/ci_tests_dev.yaml b/.github/workflows/ci_tests_dev.yaml
index e9ee33bf97f..0fc8aa3e5fa 100644
--- a/.github/workflows/ci_tests_dev.yaml
+++ b/.github/workflows/ci_tests_dev.yaml
@@ -101,7 +101,7 @@ jobs:
           pip install --pre --prefer-binary \
                         numpy pandas xarray netCDF4 packaging \
                         build dvc ipython 'pytest>=6.0' pytest-cov \
-                        pytest-doctestplus pytest-mpl sphinx-gallery tomli
+                        pytest-doctestplus pytest-mpl sphinx-gallery
 
       # Pull baseline image data from dvc remote (DAGsHub)
       - name: Pull baseline image data from dvc remote