Patch 10.0.7 releases later today in North America and servers will not be up before 3:00 PM (PDT).
(Battle.net Launcher)
We will be performing scheduled maintenance beginning on Tuesday, March 21st, 7:00 AM (PDT) and we expect the service to be available again at approximately 3:00 PM (PDT). During this time the game will be unavailable for play.