Hi Josh,
Thanks for reaching out to us, with this interesting question!
Basically there’s no way to active this kind of filter. Our Filter Bar add-on, activates a time filter (https://cloudup.com/cL1xHozD924) but I’m not sure if this is what you are looking for.
While you could create a new custom taxonomy for that I’m not sure that the best approach unless you are grouping events in general terms like filter bar does (morning, afternoon, etc). But of course it’s a valid solution. Creating a term for each hour range in the day (8-9, 9-10, 10-11, etc) might work, but it doesn’t sound practical.
Please let me know if the FilterBar solution works for you or you feel it’s an overkill for this,
Best,
Nico