You have an alert tab on the right side of your homepage. You can control the content and title of the tab with the section "Alert Box" which you can get to by going to Content > Sections > Alert Box. If you rename the box, it will not display. If you want it to display on the site, make sure the name is Alert Box.

The description field of the section controls what shows up on the tab: http://e360.d.pr/GliiRG/5yf9Fxg4

The content section controls the content that pops out: http://e360.d.pr/3Hr5by/51F94hlO