A new entry has been added to the FAQ page for WoW Realms
**My realms is down, but WoW Realms still tells me it is up. Why?**
The data that Blizzard is providing for the status of realms is always a couple of minutes behind (sometimes up to 5 minutes or more) the actual state of the physical realms you play on.
You can see the same type of delay on the Realms Status pages (US, EU, TW, KR and CN) that Blizzard are hosting themselves.