diff --git a/proto/src/system_messages.proto b/proto/src/system_messages.proto
index c4a2831..65cc17e 100644
--- a/proto/src/system_messages.proto
+++ b/proto/src/system_messages.proto
@@ -173,6 +173,9 @@
     // Package: android
     NOTE_ACCOUNT_CREDENTIAL_PERMISSION = 38;
 
+    // Inform the user their phone recently shut down due to high temperature
+    NOTE_THERMAL_SHUTDOWN = 39;
+
     // ADD_NEW_IDS_ABOVE_THIS_LINE
     // Legacy IDs with arbitrary values appear below
     // Legacy IDs existed as stable non-conflicting constants prior to the O release