Meta key relative value

I’m trying to create a list of upcoming event posts, and would like to add a meta key/value filter with a relative meta key value for a date field. I would like to do this through the UI, not custom code.

For example:
Meta Key: event_start_dt (my event start date)
Compare: Is greater than or equal to
Meta Value: today (or now, or yesterday) – this would be instead of a specific date, such as 2018-08-01.

PHP relative date formats reference: https://php.net/manual/en/datetime.formats.relative.php

Any ideas? Thanks!