At what specific point (trigger action) is the email actually sent for the Watch list notification?

When a watchlist is matched (criteria for a match is the first 3 characters of first name and full last name), the user will receive the Watch List Alert window pop up. 

The watchlist email is sent when the Alert pop up screen is closed
In order to get the watch list window pop up and send an email, configure the following:
1. E-mail server 
2. Internal Watch List Match Notification email template with valid email (restart client after changes are made)
3. Screen policy with emailWatchList flag set to 'True' for a specific visit center screen.