diff --git a/lib/microwaveprop_web/live/about_live.ex b/lib/microwaveprop_web/live/about_live.ex
index cb3cf911..bc1458fc 100644
--- a/lib/microwaveprop_web/live/about_live.ex
+++ b/lib/microwaveprop_web/live/about_live.ex
@@ -53,6 +53,15 @@ defmodule MicrowavepropWeb.AboutLive do
               >submit your contacts</.link>.
             </p>
           </div>
+          <div role="alert" class="alert alert-info">
+            <p>
+              <strong>Coverage:</strong>
+              right now this only covers the continental US. Every upstream source
+              we're using — NOAA HRRR, ASOS, IEMRE, the ITU terrain data — is
+              CONUS-only. Hawaii, Alaska, Canada, and Mexico will need different
+              data sources and aren't wired up yet.
+            </p>
+          </div>
         </div>
 
         <div class="space-y-3">