diff --git a/docs/hooks/nightly_banner.py b/docs/hooks/nightly_banner.py
new file mode 100644
index 00000000..ac32a7e9
--- /dev/null
+++ b/docs/hooks/nightly_banner.py
@@ -0,0 +1,13 @@
+import os
+
+import mkdocs.plugins
+
+
+@mkdocs.plugins.event_priority(-100)
+def on_config(config):
+    version = os.environ.get("MIKE_DOCS_VERSION")
+
+    if version == "nightly:"
+        extra = config.get("extra", {})
+        extra["nightly"] = True
+
diff --git a/docs/mkdocs.yml b/docs/mkdocs.yml
index e4c54430..c68d8fb1 100644
--- a/docs/mkdocs.yml
+++ b/docs/mkdocs.yml
@@ -147,6 +147,8 @@ extra:
     provider: mike
     default: stable
     alias: true
+  # Used for the nightly banner
+  nightly: false
 
 # Navigation
 nav:
diff --git a/docs/overrides/main.html b/docs/overrides/main.html
index 7aec83da..c96b5bb1 100644
--- a/docs/overrides/main.html
+++ b/docs/overrides/main.html
@@ -1,7 +1,7 @@
 {% extends "base.html" %}
 
 {% block announce %}
-{% if version.name == "nightly" %}
+{% if config.extra.nightly %}
 <!-- Need to reapply margin from base CSS, which is overridden in extra CSS (to fix empty banner) -->
 <div style="margin: 0.6rem auto">
     This is <strong>nightly</strong> documentation, and it may differ from stable. Please see <strong><a href="{{ '../' ~ base_url }}">here for stable documentation</a></strong>.