Tropical Cyclone Discussion

505
WTPA41 PHFO 121454
TCDCP1
 
Potential Tropical Cyclone One-C Discussion Number   1
NWS Central Pacific Hurricane Center Honolulu HI   CP012026
Issued by NWS National Hurricane Center Miami FL
500 AM HST Wed Aug 12 2026

The disturbance well to the east-southeast of the Hawaiian Islands 
is expected to become a tropical storm within the next day or so 
and be near the Islands by late Friday.  Given the potential for 
significant impacts over the Hawaiian Islands, Potential Tropical 
Cyclone advisories are being initiated at this time.  The system's 
cloud pattern is elongated from southwest to northeast with most of 
the deep convection well to the southwest of the center.  The 
disturbance currently lacks sufficiently organized convection to be 
classified as a tropical cyclone, and the Dvorak classifications 
from Honolulu are T1.0/1.0.  Scatterometer data suggests that the 
intensity is near 30 kt,

Satellite fixes indicate that the system is moving generally 
westward and the initial motion estimate is 270/9 kt.  Dynamical 
models show a mid-level high pressure system persisting to the 
north of the disturbance.  This steering pattern should result in 
a generally west-northwestward track for the next several days.  
The simple and corrected model consensus and Google DeepMind track 
predictions are in reasonable agreement, and the official forecast 
follows this guidance closely.  Given that the system is still in 
the formative stage, the precise track is still somewhat 
uncertain. 

The atmospheric and oceanic environment look conducive for gradual 
strengthening during the next few days.  Based on the intensity 
models, the system is expected to be nearing hurricane strength by 
the time it nears the Hawaiian Islands.  However, an upper-level 
low/trough could limit strengthening while the system passes near 
or over the Islands.

Key Messages:

1. The disturbance is expected to become a tropical storm later 
today or tonight and strengthen while it moves west-northwestward 
near or over the Hawaiian Islands late this week and this weekend.
Although it is too soon to specify the exact location and magnitude 
of impacts, residents should closely monitor the latest forecast 
updates and ensure that they have their preparedness plan in place. 

2. Heavy rainfall associated with the system is expected to begin 
to impact the Big Island Friday, spreading westward into Maui on 
Saturday, and across Lanai, Molokai, Oahu and Kauai on Sunday.  This 
rainfall may produce life-threatening flooding and mudslides, 
especially in areas of steep terrain.

3. There is an increasing risk of wind and wave impacts in the 
Hawaiian Islands regardless of the exact track and intensity of the 
system.  Hurricane or Tropical Storm Watches may be required for 
portions of the Hawaiian Islands tonight or early Thursday.

 
FORECAST POSITIONS AND MAX WINDS
 
INIT  12/1500Z 15.0N 141.8W   30 KT  35 MPH...POTENTIAL TROP CYCLONE
 12H  13/0000Z 15.3N 142.9W   35 KT  40 MPH...TROPICAL CYCLONE
 24H  13/1200Z 15.9N 144.1W   40 KT  45 MPH
 36H  14/0000Z 16.9N 145.9W   45 KT  50 MPH
 48H  14/1200Z 17.9N 148.3W   50 KT  60 MPH
 60H  15/0000Z 18.6N 150.8W   55 KT  65 MPH
 72H  15/1200Z 19.1N 153.2W   60 KT  70 MPH
 96H  16/1200Z 20.6N 158.3W   60 KT  70 MPH
120H  17/1200Z 22.3N 163.7W   60 KT  70 MPH