diff --git a/defaults/nginx.conf b/defaults/nginx.conf
index a3ef362..5061a5d 100644
--- a/defaults/nginx.conf
+++ b/defaults/nginx.conf
@@ -45,7 +45,7 @@ http {
 
     location ~ ^/dwd/(icons|warn_icons)/ {
       root /home/weewx/public_html;
-      expires 12h;
+      expires 1h;
     }
   }
 }