Great Stacey Stewart comment (and why he's the best they have):

Frances is forecast to remain in a low shear environment and over
increasing SSTs throughout the period. The SHIPS intensity model
now makes Frances a 113 kt major hurricane in 48 hours...since the
'self-induced' vertical shear has decreased owing to the GFS
forecast positons being closer to the official track forecast.
There will likely be several fluctuations in the intensity over the
next 5 days...but category four intensity seems likely some time
during that period...and category 5 strength is even possible

Steve