It was different each time, and then I went to my locale page and after that there were no more. I guess they got marked as "read." I assume new ones will show up again.
The switch to turn it on and off is located on your state (location) page.
At the right top you'll see one of these:
To be notified of new messages in this locale, click here.
If you do not wish to receive notification of new messages in this locale, click here.