Tropical Cyclone Discussion

768
WTPA44 PHFO 091440
TCDCP4
 
Tropical Storm Lowell Discussion Number  54
NWS Central Pacific Hurricane Center Honolulu HI   EP122026
Issued by NWS National Hurricane Center Miami FL
500 AM HST Wed Sep 09 2026
 
Infrared satellite imagery over the last several hours suggest that 
Lowell's convective shield is continuing to deteriorate as drier air 
wraps into the storm's core. The latest subjective Dvorak intensity 
estimates from HFO and JTWC classified the system at T3.0/45 kt, 
while objective estimates from UW-CIMSS ranged from 44-51 kt. Using 
these estimates and the latest satellite trends, the initial 
intensity was lowered to 50 kt. 

The initial motion is north-northwestward at 330/11 kt. A mid-level 
low centered over the north-central Pacific, along with high 
pressure to its east, is driving Lowell's north-northwestward 
motion. As the low dissipates, Lowell is expected to turn 
west-northwestward or westward along the southern flank of the high, 
then back toward the northwest as it rounds the western edge of the 
high. The track guidance exhibits significant spread late this week 
and into the weekend as Lowell becomes wedged between two mid-level 
ridges, resulting in a weak steering environment. Thus, the latest 
NHC track forecast is similar to the previous advisory, near the 
middle of the guidance envelope but given the spread there is low 
confidence in the extended forecast.

Although the SHIPS guidance indicates that sea surface temperatures 
will remain relatively steady over the next 48 h, a dry mid-level 
environment and moderate vertical wind shear should induce gradual 
weakening. The intensity guidance generally depicts further 
weakening over the next 36 h, followed by a slight increase in 
intensity over the weekend when the aforementioned mid-level low 
could briefly enhance Lowell's convection. However, because the 
broader environment remains hostile, the NHC intensity forecast 
shows gradual weakening through the entire period, with the 
intensity merely leveling off just after 36 h during the anticipated 
window of favorable trough interaction. The official NHC intensity 
forecast is unchanged from the previous advisory, and Lowell is 
still expected to become a post-tropical cyclone early next week.

KEY MESSAGES:
 
1. Post-storm safety: Follow advice of local officials and avoid
areas of downed power lines and flooding. Ensure generators are
properly ventilated and placed outside at least 20 feet away from
dwellings and garages to avoid carbon monoxide poisoning. During
clean up, be careful when using chainsaws and power tools. Drink
plenty of water to avoid heat exhaustion.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  09/1500Z 28.1N 162.3W   50 KT  60 MPH
 12H  10/0000Z 28.8N 164.0W   50 KT  60 MPH
 24H  10/1200Z 29.0N 166.6W   50 KT  60 MPH
 36H  11/0000Z 28.8N 168.8W   45 KT  50 MPH
 48H  11/1200Z 28.9N 170.4W   40 KT  45 MPH
 60H  12/0000Z 29.6N 171.2W   40 KT  45 MPH
 72H  12/1200Z 31.0N 171.7W   40 KT  45 MPH
 96H  13/1200Z 32.7N 173.4W   35 KT  40 MPH
120H  14/1200Z 34.0N 175.0W   30 KT  35 MPH...POST-TROPICAL