I’ve had it for some time but it is hard for me to understand what the forecasters know. Something is missing.
At either 250hPa (34,000ft) or 500hPa (18,400ft) you can see mid-level airflows that seem to be at work preventing Irma taking a more Westerly track, with some evidence even apparent down at 700hPa (10,000ft). Not saying they’re 100% of the reason for the change in heading, but certainly appear to be contributing. An interesting piece to a very large puzzle.