000
WTPZ44 KNHC 072037
TCDEP4
 
Hurricane Bonnie Discussion Number  41
NWS National Hurricane Center Miami FL       EP042022
200 PM PDT Thu Jul 07 2022
 
Bonnie's satellite presentation has improved since this morning 
with the formation of a well-defined 15-n mi-wide eye and cloud 
tops as cold as -70 to -75 degrees Celsius.  The hurricane has 
seemingly not weakened, and the initial intensity remains 80 kt as 
a blend of Dvorak estimates of 5.0 and 4.0 from TAFB and SAB, 
respectively.  Bonnie is forecast to move over increasingly cooler 
waters and into a drier, more stable atmosphere within the next day 
or so, and those factors should induce a resumption of weakening.  
Given the hurricane's improved structure, the official intensity 
forecast is a little higher than the IVCN consensus at 12 hours, 
but then falls in line with the consensus guidance after that time. 
Bonnie could lose all organized deep convection by Saturday, and it 
is therefore shown as a post-tropical cyclone in 48 hours.  The 
post-tropical low is expected to degenerate into a trough by day 4 
(Monday).

The initial motion is a little faster toward the west-northwest 
(285/13 kt).  The track guidance is more tightly packed than 
normal, and there is high confidence that Bonnie will turn westward 
and accelerate tonight, reaching its fastest motion Friday night.  
The weakening low is expected to continue on a quick westward 
track south of the low-level ridge until it dissipates.  The new 
NHC track forecast is right on top of the previous prediction.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/2100Z 17.7N 115.3W   80 KT  90 MPH
 12H  08/0600Z 18.1N 117.6W   75 KT  85 MPH
 24H  08/1800Z 18.7N 121.0W   60 KT  70 MPH
 36H  09/0600Z 19.3N 124.7W   50 KT  60 MPH
 48H  09/1800Z 19.6N 128.3W   40 KT  45 MPH...POST-TROPICAL
 60H  10/0600Z 19.8N 131.9W   35 KT  40 MPH...POST-TROPICAL
 72H  10/1800Z 19.9N 135.2W   30 KT  35 MPH...POST-TROP/REMNT LOW
 96H  11/1800Z...DISSIPATED
 
$$
Forecaster Berg