Hurricane Isaac Discussion Number   7
NWS National Hurricane Center Miami FL       AL102024
1100 AM AST Fri Sep 27 2024

Isaac is holding steady this morning.  Geostationary satellite data 
has shown consistent periodic bursts of convection wrapping around a 
small eye.  Subjective and objective Dvorak estimates range widely 
from 35 kt to 73 kt and the initial intensity is held at 65 kt for 
this advisory, closest to the SAB classification. 

The hurricane is moving eastward at 12 kt.  Isaac is moving along 
the northern periphery of a mid-level ridge  and should gradually 
turn to the east-northeast over the next couple of days.  Models are 
more in agreement this cycle and show a more northeastward turn on 
days 4 and 5 as Isaac interacts with an upper-level trough located 
to its east.  The latest track forecast is similar to the previous 
forecast through 72 h and slightly to the north at forecast periods 
beyond.

Isaac could still strengthen further over the next day or so.  While 
the vertical wind shear is expected to be strong-to-moderate, the 
upper-level divergence is forecast to increase and sea surface 
temperature should be relatively sufficient.  Beyond a day or so, 
oceanic and environmental conditions become less conducive, which 
should begin to weaken Isaac by Saturday night or Sunday.  The 
official intensity forecast is very similar to previous advisory, 
with a peak intensity of 75 kt by Saturday and the cyclone becoming 
extratropical by early next week.  However, global models show the 
system losing its deep convection by Monday, and the official 
forecast now predicts Isaac becoming a post-tropical cyclone at that 
point. 


FORECAST POSITIONS AND MAX WINDS

INIT  27/1500Z 37.4N  46.8W   65 KT  75 MPH
12H  28/0000Z 38.1N  44.2W   70 KT  80 MPH
24H  28/1200Z 39.4N  40.9W   75 KT  85 MPH
36H  29/0000Z 41.0N  38.4W   75 KT  85 MPH
48H  29/1200Z 42.4N  36.6W   70 KT  80 MPH
60H  30/0000Z 43.7N  35.1W   60 KT  70 MPH
72H  30/1200Z 44.8N  33.0W   55 KT  65 MPH...POST-TROPICAL
96H  01/1200Z 48.0N  29.6W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  02/1200Z 52.1N  25.0W   35 KT  40 MPH...POST-TROP/EXTRATROP

$$
Forecaster Bucci