There may be times when you are updating an existing WordPress site or theme, or setting up a new one when you don’t want visitors to see errors or ugly content in flux. Maintenance Mode is a simple plugin to take care of this.
It adds a splash page to your blog that lets visitors know your blog is down for maintenance. Logged in administrators get full access to the blog including the front-end.
Visitors will see a message like “Maintenance Mode – SITE is currently undergoing scheduled maintenance. Please try back in 60 minutes. Sorry for the inconvenience.”
Check it out here.