Tropical Cyclone Discussion

792
WTPZ41 KNHC 030857
TCDEP1
 
Hurricane Karina Discussion Number  28
NWS National Hurricane Center Miami FL       EP112026
1100 PM HST Wed Sep 02 2026

While Karina continues to exhibit an annular appearance with a 
large ring of deep convection, its cloud-top temperatures have been 
gradually warming.  The eye of the hurricane has also expanded to a 
diameter of 30 to 40 n mi.  Subjective Dvorak classifications from 
TAFB give a current intensity estimate of 102 kt and objective 
intensity estimates from UW-CIMSS range from 95 to 109 kt.  The 
advisory intensity is set at 105 kt, near the higher end of the 
estimates.  A couple of recent scatterometer overpasses more or 
less confirmed the previously estimated 34- and 50-kt wind radii 
for the hurricane.

Karina continues with a west-northwestward motion at around 
285/10 kt.  The system should maintain this motion for the next 48 
hours or so, under the influence of a subtropical ridge to its 
north.   Thereafter, a mid-tropospheric cyclone to the north 
of the Hawaiian Islands is expected to cause a slight northwestward 
bend in the track.  The official forecast is very similar to the 
previous NHC track.  This is fairly close to the latest Google 
DeepMind and HFIP Corrected consensus predictions, which have 
proved to be quite reliable track guidance so far.

Vertical wind shear is forecast to remain low for the next 48 hours 
or so, with significantly increasing southwesterly shear likely 
later in the forecast period.  Karina should move over gradually 
cooling ocean waters for the next several days, with the low- to 
mid-level air mass becoming increasingly dry.  Given these 
expected environmental conditions, Karina should weaken during the 
forecast period, and become a post-tropical cyclone in 5 days or 
sooner.  The official intensity forecast is a little above the 
model consensus for the next 48 hours in consideration of the 
annular structure, but is close to the overall model guidance mean
thereafter.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  03/0900Z 19.6N 135.7W  105 KT 120 MPH
 12H  03/1800Z 20.0N 137.1W  100 KT 115 MPH
 24H  04/0600Z 20.4N 138.9W   90 KT 105 MPH
 36H  04/1800Z 20.9N 140.5W   80 KT  90 MPH
 48H  05/0600Z 21.4N 142.0W   70 KT  80 MPH
 60H  05/1800Z 22.1N 143.0W   60 KT  70 MPH
 72H  06/0600Z 23.0N 144.1W   55 KT  65 MPH
 96H  07/0600Z 24.6N 147.0W   45 KT  50 MPH
120H  08/0600Z 26.3N 150.8W   30 KT  35 MPH...POST-TROPICAL