diff --git a/defaults/nginx.conf b/defaults/nginx.conf
index a8ff289..53bcff7 100644
--- a/defaults/nginx.conf
+++ b/defaults/nginx.conf
@@ -47,8 +47,9 @@ http {
       expires modified 1h;
     }
 
-    location /dwd {
-      root /home/weewx/public_html/dwd;
+    location ~ ^/dwd/(icons|warn_icons)/ {
+      root /home/weewx/public_html;
+      expires 12h;
     }
   }
 }