Issued at 800 PM PDT Wed Aug 26 2026 
000
WTPZ44 KNHC 270233
TCDEP4
 
Post-Tropical Cyclone Iselle Discussion Number  15
NWS National Hurricane Center Miami FL       EP092026
800 PM PDT Wed Aug 26 2026

Iselle continues to have no deep convective organization this 
evening with the low-level center still fully exposed due to dry air 
and moderate wind shear. With the lack of convection occuring, 
Iselle is now considered to have become a Post-Tropical Cyclone. The 
most recent TAFB Dvorak fix has 1.5/25 kt and the objective 
satellite intensity estimates are in the range of 25-43 kt. Based on 
that data, the current NHC initial intensity has been set to 30 kt.

Iselle should continue to move west-northwestward over the next 
couple of days, steered by a mid-level ridge to the north of the 
cyclone. Increasing wind shear, cooler sea surface temperatures, and 
a drier air mass will continue to weaken the system. The 
post-tropical remnant low is expected to gradually spin down 
and open into a trough in about 2 to 3 days. However, it still 
remains possible that the cyclone could spin down even sooner. Very 
minor adjustments were made to the previous NHC track and intensity 
forecasts.

For additional information on the remnant low please see High Seas
Forecasts issued by the National Weather Service, under AWIPS
header NFDHSFEPI, WMO header FZPN01 KWBC, and on the web at
ocean.weather.gov/shtml/NFDHSFEPI.php

 
FORECAST POSITIONS AND MAX WINDS
 
INIT  27/0300Z 23.0N 125.9W   30 KT  35 MPH...POST-TROP/REMNT LOW
 12H  27/1200Z 23.6N 127.2W   25 KT  30 MPH...POST-TROP/REMNT LOW
 24H  28/0000Z 24.3N 128.8W   20 KT  25 MPH...POST-TROP/REMNT LOW
 36H  28/1200Z 24.8N 130.2W   20 KT  25 MPH...POST-TROP/REMNT LOW
 48H  29/0000Z 25.3N 131.6W   20 KT  25 MPH...POST-TROP/REMNT LOW
 60H  29/1200Z...DISSIPATED
 
$$
Forecaster Katz/Hagen/Papin


Source: Post-Tropical Cyclone Iselle Forecast Discussion Number 15