diff --git a/.github/workflows/ci_workflows.yml b/.github/workflows/ci_workflows.yml
index e85c85f7d..fb56dcf2e 100644
--- a/.github/workflows/ci_workflows.yml
+++ b/.github/workflows/ci_workflows.yml
@@ -79,10 +79,10 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - name: (Allowed Failure) Python 3.11 with remote data and dev version of key dependencies
+          - name: (Allowed Failure) Python 3.12 with remote data and dev version of key dependencies
             os: ubuntu-latest
-            python: '3.11'
-            toxenv: py311-test-devdeps
+            python: '3.12-dev'
+            toxenv: py312-test-devdeps
             toxposargs: --remote-data=any
 
     steps:
diff --git a/tox.ini b/tox.ini
index 7a8101bf7..603ab0308 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 envlist =
-    py{38,39,310,311}-test{,-devdeps,-oldestdeps,-predeps}{,-cov,-external}
+    py{38,39,310,311,312}-test{,-devdeps,-oldestdeps,-predeps}{,-cov,-external}
     linkcheck
     codestyle
 requires =
@@ -66,6 +66,8 @@ extras =
     !oldestdeps: jwst
 
 commands =
+    # Force numpy-dev after matplotlib downgrades it (https://github.com/matplotlib/matplotlib/issues/26847)
+    devdeps: python -m pip install --pre --upgrade --extra-index-url https://pypi.anaconda.org/scientific-python-nightly-wheels/simple numpy
     pip freeze
     !cov: pytest --pyargs specutils {toxinidir}/docs {posargs}
     cov: pytest --pyargs specutils {toxinidir}/docs --cov specutils --cov-config={toxinidir}/setup.cfg {posargs}