From 8/31 5pm EST discussion...intensity forecasting is a pain in the butt . none of the guidance, even the most aggressive, had a 50kt increase in max wind speed in less than 24hr.
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Hurricane Irma Discussion Number 6
NWS National Hurricane Center Miami FL AL112017
500 PM AST Thu Aug 31 2017
Irma has become an impressive hurricane with intense eyewall
convection surrounding a small eye. Satellite estimates continue to
rapidly rise, and the Dvorak classifications from both TAFB & SAB
support an initial wind speed of 100 kt. This is a remarkable 50-kt
increase from yesterday at this time.
Microwave and satellite data suggest that an eyewall replacement
cycle could be starting. This isn't surprising given how small the
eye is, and will probably be the first of many eyewall cycles for
this hurricane. Overall, Irma should be in a low-shear environment
for several days, with the intensity controlled by eyewall cycles
and the moderately warm SSTs along the path. Thus the forecast
intensity is leveled off for the next 2 days. After the weekend,
Irma should be moving over much warmer water, with SSTs forecast to
be 29C at the end of the period. All indications are for Irma to be
strengthening by the end of the forecast period, with the NHC
prediction adjusted slightly upward from the previous one, in line
with the extremely low pressures forecast by the global and regional
hurricane models at that time.