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Tropical Storm Ivo Discussion Number   9
NWS National Hurricane Center Miami FL       EP092025
200 PM MST Fri Aug 08 2025
 
Ivo's structure has become more organized during the past few 
hours, with inner core banding becoming more pronounced.  Recent 
WSF-M and GMI microwave data were helpful in confirming the 
improved structure, and also showed that Ivo's center was located a 
little farther south than previously estimated.  Despite the 
improved structure, there is a wide range in intensity estimates.  
Subjective Dvorak estimates from TAFB and SAB range from 55-65 kt, 
while objective numbers from UW-CIMSS are stuck at 40-45 kt.  To 
add to the quandary, ASCAT data only showed maximum winds of 35 kt, 
but it is highly likely that Ivo is too small for the instrument to 
effectively sample its maximum winds.  For now, Ivo's maximum winds 
are set to 55 kt.

The storm has turned westward and continues to slow down with an 
initial motion of 275/11 kt.  A westward to west-northwestward 
trajectory is forecast to continue for the next several days as 
strong mid-level ridging remains entrenched to the north.  The NHC 
track forecast has been shifted south of the previous prediction to 
account for the adjustment of the initial position, but otherwise 
it is very close to the various multi-model consensus aids.

Some additional strengthening is anticipated during the next 12-24 
hours while Ivo remains in an unstable environment with upper-level 
divergence, and over waters warmer than 26 degrees Celsius.  
While not explicitly shown in the forecast, Ivo could still 
become a hurricane between the nominal forecast times.  All of 
the aforementioned environmental factors turn detrimental in about 
36 hours, at which point more significant weakening is expected to 
begin.  Ivo could lose its deep convection and become post-tropical 
in about 60 hours.  Dissipation is now shown by day 4 in line with 
the ECWMF, UKMET, and Canadian model solutions, with the GFS being 
an outlier and continuing the remnant low westward for another day 
or so after that.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  08/2100Z 20.4N 111.2W   55 KT  65 MPH
 12H  09/0600Z 20.5N 112.5W   60 KT  70 MPH
 24H  09/1800Z 20.7N 114.0W   60 KT  70 MPH
 36H  10/0600Z 21.0N 115.7W   55 KT  65 MPH
 48H  10/1800Z 21.5N 117.5W   45 KT  50 MPH
 60H  11/0600Z 21.8N 119.4W   35 KT  40 MPH...POST-TROPICAL
 72H  11/1800Z 21.9N 121.5W   30 KT  35 MPH...POST-TROP/REMNT LOW
 96H  12/1800Z...DISSIPATED
 
$$
Forecaster Berg
 
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