mcowger - I'm not exactly sure how to find that. I don't have direct host access.
UPDATE - migrating the guest to a completely new host in a different cluster has brought the disk latency back into normal ranges. I attached a new screen grab. Perhaps we're seeing a communication bottleneck on that fibre channel. We're having our storage engineer look into it.
I'll post more updates as we discover the root cause. Or if we start having the problem again!
Thanks for everyone's help,
--Alyssa