Irma is the new tropical storm on the map and it is an impressive looking system. It developed very quickly over night and this morning and it is evident on the satellite loop that Irma is a big system with a classic satellite signature of a strengthening tropical storm. It is alos very far away at the moment as it is west of the Cabo Verde Island and moving toward the west. It will take many days for Irma to cross the Atlantic and where it winds up and how far west it gets is going to depend on the Atlantic ridge of high pressure that is forecast to build over the next 5 days.
With regards to strengthening there is an upper low in the Atlantic well to the northwest of Irma. This system is meandering northward and is not all that strong. As long as this remains the case conditions across the tropical Atlantic shoudl remain favorable for strengthening. There is some dry air evident in the Central Tropical Atlantic at the moment but it does not look like it presents a big challenge. It might slow the strengthening rate some for a time but it should not hinder this system from becoming a hurricane and possibly a major hurricane.
Weather models are all showing a very strong ridge building in the Atlantic. The GFS model and European model are not that much different in their profiles of the upper atmosphere at the moment..READ MORE AT http://www.meteorologistjoecioffi.com/index.php/2017/08/30/irma-destinty-depends-atlantic-ridge/