There is no doubt that Hurricane Katia is a good looking strong system. Satellite imagery clearly shows a well organized storm, with an eye at its center, good feeder banding and nice outflow.
Intensity forecasting is one of the most difficult things to do but as of now, conditions appear favorable for Katia to continue growing in strength. By the end of the week it should be out of the warm water stream that is feeding her now, and she should begin to lose her intensity.
It will continue to head on a northwesterly track over the next few days as high pressure builds back toward the west. This should keep Katia aiming for the East Coast. Models are in fair agreement that by mid week, the high will move back into the Atlantic and permit Katia to turn north. The system may get uncomfortably close to the US before turning away.
This is the official forecast cone. By day four, Katia should make a turn North, if it doesn't, Katia could impact the Northeast. They are still cleaning up from Irene's wrath.