Adding a graphic frame to a reference frame outside the column

Another option is using pictogram fonts. This is the free font "Tables". The page setup uses Sidehead. A paragraph tag with the Tables font sits in the Sidehead.When you press Enter, the Next Tag settings leads you to the warning text tag and from there to the body text tag.

Hi Lisa:

That doesn't work, unfortunately. But you could create the alert box with the anchored frame sitting outside the column on the reference page. And then put both into a named graphic frame. (Create one for each alert type.)

This will allow you to quickly add the alert message by assigning a paragraph style using rule above paragraph or rule below paragraph. But the referenced frame will be inside the template frame, no matter what. 

You could define a side-head column to make it look like it is outside of the frame, however, and set the paragraph style to Across all Columns and Side-heads.

Borders visible

Borders hidden

~Barb