Hey there! I am having the same problem, After HOT update, i am experiencing drastic fps drops in all areas.
My Specs are. CPU: Intel i5 4690k GPU: R9 390 RAM: 8gb
Though i think that GW2 usually have fps drops after some updates.
If so..they should resolve the issue after a few Patches, as we are still Early into the HOT release.
Is anyone else having this issue?