Jonathan Bardo

<p><strong>Note: This plugin only works with WordPress 4.2 or higher</strong></p>
<p>This plugin will enable the site administrator to easily create an admin message present on all pages. The admin has the option to let the user dismiss the message for the duration of his session.</p>


Admin User Message

This does just what I want. Thanks for making it. :)
It's definitely better than https://wordpress.org/plugins/admin-screen-messages
You might want to also tag it as:
https://wordpress.org/plugins/tags/admin-message



Perfect

Add message to users of your site. Choose wheter they can dismiss it or not.

WEN Solutions

<p>Notice bar is simple but powerful plugin to create and display custom Notice bars in WordPress websites. It helps website admins to effectively convey notices, information & messages to their visitors swiftly. With user friendly interface, tons of options to toggle and multiple notice types, Notice Bar is undoubtedly one of  best notice bar plugin for WordPress websites.</p>
<h4>Some Useful Links</h4>
<ul>
<li>Plugin : <a href="http://wensolutions.com/plugins/notice-bar/" rel="nofollow ugc">Homepage</a></li>
<li><a href="https://wensolutions.com/contact/" rel="nofollow ugc">Support Forum</a></li>
</ul>


Notice Bar

Made it useless for me. But the message works, so 3 stars.

Can't add link

A easy plugin to show multiple notice bar in WordPress sites.

Admin User Message vs Notice Bar