It appears, according to the 11 AM Discussion on the NHC website, that there are two distinct groups of thought on Irma, one taking it more north and one staying south.

"There is a noticeable clustering of guidance by day 5, with the ECMWF, HWRF and
corrected-consensus models to the south, and the UKMET, GFS, CTC and
HMON to the north. Since Irma is forecast to be a vertically deep
cyclone, it seems more likely to respond to the northerly flow from
the upper-level low, which leads me to believe the track will be on
the southern side of the guidance. Thus, the forecast will stay
similar to the previous one, very close to the southern cluster
mentioned above. "

Carol Hill