Tropical Cyclone Discussion

866
WTPZ41 KNHC 021435
TCDEP1
 
Hurricane Karina Discussion Number  25
NWS National Hurricane Center Miami FL       EP112026
500 AM HST Wed Sep 02 2026
 
Karina continues to exhibit a circular, annular structure on 
proxy-vis and infrared satellite imagery. The hurricane has a 
well-defined, warm 30 n mi eye, with deep convection wrapping around 
the inner core. The latest objective and subjective satellite 
intensity estimates from UW-CIMSS and TAFB range from 109 to 137 kt. 
Based on the steady satellite appearance and a range of these 
estimates, the intensity is held at 125 kt.
 
The hurricane continues to move westward at an estimated motion of 
285/9 kt. The steering flow remains unchanged, with the system 
expected to continue moving westward to west-northwestward along the 
southern side of a ridge located to the north. As a mid-level low 
moves north of the Hawaiian islands the ridge will weaken, and the 
system should move northwestward. The latest NHC track is similar 
to the previous and lies close to the HCCA and GDMI aids.
 
Karina remains over marginally warm waters sea surface temperatures, 
tracking roughly parallel to the 26-27C isotherm. Wind shear also 
remains low during the next few days, before increasing beyond 72 h. 
Some fluctuations in intensity are possible today, before a gradual 
weakening trend is expected. In about 2-3 days, the system should 
begin to move into a drier environment and over cooler SSTs, 
although given the annular structure, weakening is anticipated to be 
more gradual than normal. The NHC intensity guidance is higher than 
most of the guidance, given the annular structure, and shows a 
gradual rate of weakening during the early part of the forecast 
period before a more steady rate of weakening by the end of the 
period. Global infrared simulated satellite imagery shows that 
Karina will struggle to produce organized deep convection by day 5, 
due to the shear and dry air, and the NHC forecast now calls for the 
system to become post-tropical at that time.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  02/1500Z 18.8N 132.8W  125 KT 145 MPH
 12H  03/0000Z 19.2N 134.2W  125 KT 145 MPH
 24H  03/1200Z 19.7N 136.2W  120 KT 140 MPH
 36H  04/0000Z 20.1N 138.2W  110 KT 125 MPH
 48H  04/1200Z 20.5N 140.0W   95 KT 110 MPH
 60H  05/0000Z 21.0N 141.7W   85 KT 100 MPH
 72H  05/1200Z 21.7N 143.1W   70 KT  80 MPH
 96H  06/1200Z 23.6N 145.1W   60 KT  70 MPH
120H  07/1200Z 26.0N 148.0W   45 KT  50 MPH...POST-TROPICAL