Forcing digests

I have a list that often will go a day or so without any posts, which unhinges the next 2pm digest delivery. I have cronlist running daily, but have not figured out how to work .digest.force into the daily schedule. I've created it manually a few times and found that this helps the digest delivery. But how do I automatically create this file on a daily basis? Is it something that can be added to the cronlist or flush_digest scripts? Or should it be a separate cron job? How do I do this? TIA linda