000
WTPA42 PHFO 280232
TCDCP2
 
Hurricane Nolo Discussion Number  30
NWS Central Pacific Hurricane Center Honolulu HI   EP152026
Issued by NWS National Hurricane Center Miami FL
500 PM HST Sun Sep 27 2026

The satellite presentation of Nolo has continued to improve this 
afternoon. Recent visible and infrared imagery reveals a thick, 
symmetric ring of deep, cold convection completely surrounding a 
warm eye, with a temperature nearing 20C. Furthermore, the cyclone 
is largely devoid of outer rainbands, suggesting that Nolo is taking 
on the characteristics of an annular hurricane, which is further 
supported by recent AMSR3 microwave images. Subjective Dvorak and 
objective intensity estimates have steadily risen during the past 
several hours. The latest subjective Dvorak classifications from the 
JTWC and HFO are T6.0 and T6.5, respectively, while objective 
estimates from UW-CIMSS currently range from 113 to 131 kt. Based on 
a blend of these estimates and recent satellite trends, the initial 
intensity is set at 125 kt for this advisory.
 
The initial motion is estimated to be west-northwestward, or 285/10 
kt. A gradual turn toward the northwest is forecast tonight, and 
this general motion should continue through Tuesday as Nolo is 
steered between a mid- to upper-level low to its northwest and a 
mid-level ridge located north of the main Hawaiian Islands. During 
the latter half of the forecast period, the cyclone is expected to 
turn back toward the west as it moves around the northern periphery 
of the low. The latest official track forecast is very similar to 
the previous advisory and lies in agreement with the HCCA and Google 
DeepMind aids.
 
Nolo is currently taking advantage of a highly favorable environment 
characterized by low vertical wind shear and warm sea surface 
temperatures. This should allow for continued strengthening in the 
short term, with internal dynamics such as eyewall replacement 
cycles likely dictating any intensity fluctuations over the next 24 
to 36 hours. Beyond that time, vertical wind shear is forecast to 
increase as the system interacts with the upper-level low, which 
should induce a weakening trend. However, given its developed 
annular structure, Nolo will likely be more resilient to this 
adverse environment and decay at a slower rate than typical tropical 
cyclones. Toward the end of the forecast period, the shear is 
expected to decrease. Because the cyclone will remain over warm 
SSTs, some restrengthening is possible by day 4 or 5, although there 
is some bifurcation in the models at that time. To account for both 
the recent strengthening trend and the historically slow decay rate 
of annular hurricanes, the official intensity forecast remains near 
or above the high end of the guidance suite in the short term, then 
falling closer towards the HCCA intensity aid in the middle to 
latter part of the forecast period.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  28/0300Z 16.3N 160.3W  125 KT 145 MPH
 12H  28/1200Z 16.9N 161.7W  140 KT 160 MPH
 24H  29/0000Z 18.3N 163.1W  130 KT 150 MPH
 36H  29/1200Z 20.2N 163.8W  115 KT 130 MPH
 48H  30/0000Z 21.9N 163.8W  100 KT 115 MPH
 60H  30/1200Z 22.8N 163.7W   80 KT  90 MPH
 72H  01/0000Z 23.0N 164.2W   65 KT  75 MPH
 96H  02/0000Z 23.7N 166.4W   60 KT  70 MPH
120H  03/0000Z 24.3N 168.3W   65 KT  75 MPH
 
$$
Forecaster Kelly