diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index f37ed0bf..17f938e3 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -38,19 +38,20 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - tox-env: py38-linux
-            python-version: "3.8"
-            os: ubuntu-latest
-          - tox-env: py38-macos
-            python-version: "3.8"
-            os: macos-latest
           - tox-env: py39-linux
             python-version: "3.9"
             os: ubuntu-latest
+          - tox-env: py39-macos
+            python-version: "3.9"
+            os: macos-latest
           - tox-env: py310-linux-upstream
             python-version: "3.10"
             os: ubuntu-latest
-            upstream-branch: "from-official-git"
+            upstream-branch: "main"
+          - tox-env: py310-macos-upstream
+            python-version: "3.10"
+            os: macos-latest
+            upstream-branch: "main"
           - tox-env: py311-linux
             python-version: "3.11"
             os: ubuntu-latest
@@ -60,6 +61,9 @@ jobs:
           - tox-env: py312-linux
             python-version: "3.12"
             os: ubuntu-latest
+          - tox-env: py312-macos
+            python-version: "3.12"
+            os: macos-latest
     steps:
     - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
@@ -107,15 +111,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        include:
-          - os: ubuntu-latest
-            python-version: "3.9"
-          - os: ubuntu-latest
-            python-version: "3.10"
-          - os: ubuntu-latest
-            python-version: "3.11"
-          - os: macos-latest
-            python-version: "3.9"
+        os: [ubuntu-latest, macos-latest]  # windows-latest  # disabled until xesmf is available
+        python-version: ["3.9", "3.10", "3.11", "3.12"]
     defaults:
       run:
         shell: bash -l {0}
@@ -141,7 +138,7 @@ jobs:
           echo "micromamba: $(micromamba --version)"
       - name: Install RavenPy
         run: |
-          pip install -e ".[dev]"
+          python -m pip install -e ".[dev]"
       - name: List installed packages
         run: |
           conda list
diff --git a/HISTORY.rst b/HISTORY.rst
index 19ed6b23..40003a14 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -4,14 +4,17 @@ History
 
 0.14.0 (2024--soon)
 -------------------
-* Added support for Python3.12.
+* Added support for Python 3.12 and dropped support for Python3.8.
 * Upgraded `raven-hydro` to v0.3.0 and `RavenHydroFramework` to v3.8.
+* `ravenpy` now requires `xclim` >= v0.48.2, `xarray` >= v2023.11.0, and `pandas` >= 2.2.0.
 
 Internal changes
 ^^^^^^^^^^^^^^^^
 * Updated GitHub publishing workflows to use Trusted Publisher for TestPyPI/PyPI releases.
 * Added Dependabot to keep dependencies up-to-date.
 * Now using step-security/harden-runner action to harden GitHub Actions runners.
+* Adjusted GitHub Workflows to test against Python 3.9, 3.10, 3.11, and 3.12.
+* Updated the build-system requirements when testing with `tox` to use newer `setuptools` and `wheel` versions when building `gdal`.
 
 0.13.0 (2024-01-10)
 -------------------
diff --git a/environment.yml b/environment.yml
index d3c35427..a246da57 100644
--- a/environment.yml
+++ b/environment.yml
@@ -3,7 +3,7 @@ channels:
   - conda-forge
   - defaults
 dependencies:
-  - python >=3.8,<3.13
+  - python >=3.9,<3.13
   - raven-hydro ==0.2.4
   - libgcc  # for mixing raven-hydro from PyPI with conda environments
   - affine
@@ -26,9 +26,9 @@ dependencies:
   - lxml
   - matplotlib
   - netcdf4
-  - numpy <1.25
+  - numpy
   - owslib <0.29.0  # see: https://github.com/geopython/OWSLib/issues/871
-  - pandas <2.2.0  # xclim <0.48.0 is incompatible with pandas >=2.2.0
+  - pandas >=2.2.0
   - pint >=0.20
   - platformdirs
   - pre-commit
@@ -44,7 +44,7 @@ dependencies:
   - spotpy
   - statsmodels
   - typing_extensions
-  - xarray >=2022.12.0,<2023.9.0  # xarray v2023.9.0 is incompatible with xclim<=0.45.0
-  - xclim >=0.43,<0.48
+  - xarray >=2023.11.0  # xarray v2023.9.0 is incompatible with xclim<=0.45.0
+  - xclim >=0.48.2
   - xesmf
   - xskillscore
diff --git a/pyproject.toml b/pyproject.toml
index 1aa89fce..ba5ca462 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -12,7 +12,7 @@ maintainers = [
   {name = "Trevor James Smith", email = "smith.trevorj@ouranos.ca"}
 ]
 readme = {file = "README.rst", content-type = "text/x-rst"}
-requires-python = ">=3.8.0"
+requires-python = ">=3.9.0"
 keywords = ["raven", "raven-hydro", "hydrology", "gis", "analysis", "modelling"]
 license = {file = "LICENSE"}
 classifiers = [
@@ -24,7 +24,6 @@ classifiers = [
   "Natural Language :: English",
   "Operating System :: OS Independent",
   "Programming Language :: Python :: 3 :: Only",
-  "Programming Language :: Python :: 3.8",
   "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
@@ -38,52 +37,52 @@ dynamic = ["description", "version"]
 dependencies = [
   "cftime",
   # cf-xarray is differently named on conda-forge
-  "cf-xarray[all]<0.8.5; python_version == '3.8'",
-  "cf-xarray[all]; python_version >= '3.9'",
-  "climpred>=2.4.0",
+  "cf-xarray[all]",
+  "climpred >=2.4.0",
   "dask",
   "haversine",
   "h5netcdf",
   "matplotlib",
   "netCDF4",
-  "numpy<1.25",
-  "owslib>=0.24.1,<0.29", # see: https://github.com/geopython/OWSLib/issues/871
-  "pandas<2.0.0; python_version == '3.8'",
-  "pandas<2.2.0; python_version >= '3.9'",
-  "pint>=0.20",
+  "numpy",
+  "owslib >=0.24.1,<0.29", # see: https://github.com/geopython/OWSLib/issues/871
+  "pandas >=2.2.0",
+  "pint >=0.20",
   "platformdirs",
-  "pydantic>=2.0",
+  "pydantic >=2.0",
   "pymbolic",
-  "raven-hydro==0.2.4",
+  "raven-hydro ==0.2.4",
   "requests",
   "scipy",
   "spotpy",
   "statsmodels",
   "typing-extensions",
-  "xarray>=2022.12.0,<2023.9.0", # xarray v2023.9.0 is incompatible with xclim<=0.45.0
-  "xclim>=0.43.0,<0.48.0",
+  "xarray >=2023.11.0",
+  "xclim >=0.48.2",
   "xskillscore"
 ]
 
 [project.optional-dependencies]
 dev = [
-  "black>=24.1.1",
+  "black >=24.2.0",
   "bump2version",
   "coverage",
   "coveralls",
   "filelock",
-  "flake8>=7.0.0",
+  "flake8 >=7.0.0",
   "flit",
   "holoviews",
   "hvplot",
-  "isort>=5.13.2",
+  "isort >=5.13.2",
   "mypy",
   "pre-commit",
   "pytest",
   "pytest-cov",
-  "pytest-xdist>=3.2.0",
+  "pytest-xdist >=3.2.0",
+  "setuptools >=68.0",
   "tox",
-  "watchdog"
+  "watchdog",
+  "wheel >=0.42.0"
 ]
 docs = [
   "autodoc-pydantic",
@@ -94,7 +93,7 @@ docs = [
   # Needed for notebooks/HydroShare_integration.ipynb
   # See: https://github.com/CSHS-CWRA/RavenPy/pull/326
   # "hsclient",
-  "intake",
+  "intake <2.0.0",
   "intake-esm",
   "intake-xarray",
   "ipykernel",
@@ -114,17 +113,17 @@ docs = [
   "sphinx-click",
   "sphinx-codeautolink",
   "sphinx-copybutton",
-  "sphinx-rtd-theme>=1.0",
+  "sphinx-rtd-theme >=1.0",
   "xesmf"
 ]
 gis = [
   "affine",
-  "fiona>=1.9",
-  "geopandas>=0.13.0",
+  "fiona >=1.9",
+  "geopandas >=0.13.0",
   "gdal",
   "lxml",
   "pyogrio",
-  "pyproj>=3.0.0",
+  "pyproj >=3.0.0",
   "rasterio",
   "rioxarray",
   "shapely"
diff --git a/ravenpy/utilities/coords.py b/ravenpy/utilities/coords.py
index ec3632ae..d9454042 100644
--- a/ravenpy/utilities/coords.py
+++ b/ravenpy/utilities/coords.py
@@ -97,7 +97,7 @@ def infer_scale_and_offset(
             multi, base, start_anchor, _ = parse_offset(freq)
             if base in ["M", "Q", "A"]:
                 raise ValueError(f"Irregular time frequency for input data {da}")
-            real_source = source / multi / units(FREQ_UNITS[base])
+            real_source = source / multi / units(FREQ_UNITS.get(base, base))
             scale, offset = units_transform(real_source, target)
         else:
             raise NotImplementedError(f"data_type: {data_type}")
diff --git a/tox.ini b/tox.ini
index d1f705d2..15119254 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,7 +7,8 @@ envlist =
 requires =
     flit
     pip >=23.0
-    setuptools >=63.0,<65.6
+    setuptools >=68.0
+    wheel >=0.42.0
 opts =
     -vv
 
@@ -55,7 +56,7 @@ install_command =
 deps =
     # numpy must be present in python env before GDAL is installed
     numpy
-    gdal == {env:GDAL_VERSION}
+    gdal[numpy] == {env:GDAL_VERSION}
 commands_pre =
     python -m pip list
     - python -m pip check
@@ -64,7 +65,7 @@ commands =
     # Rebuild netcdf4 on Linux due to errors in new version (https://github.com/Unidata/netcdf4-python/issues/1192)
     # linux: python -m pip install --upgrade --force-reinstall --no-deps --no-cache-dir netcdf4==1.6.4 --no-binary netcdf4
     # Rebuild GDAL in order to gain access to GDAL system-level objects
-    python -m pip install --upgrade --force-reinstall --no-deps --no-cache-dir gdal=={env:GDAL_VERSION}.* --no-binary gdal
+     python -m pip install --upgrade --force-reinstall --no-deps --no-cache-dir --no-build-isolation gdal[numpy]=={env:GDAL_VERSION}.*
     # Install raven-hydro from the upstream branch
     upstream: python -m pip install --upgrade --force-reinstall --no-deps --no-cache-dir git+https://github.com/Ouranosinc/raven-hydro.git@{env:UPSTREAM_BRANCH}
     # Run tests