546 
WTPZ43 KNHC 061457
TCDEP3
 
Tropical Storm Henriette Discussion Number  10
NWS National Hurricane Center Miami FL       EP082025
500 AM HST Wed Aug 06 2025

Henriette has changed very little this morning.  It continues to 
produce a relatively small area of deep convection, with cold cloud 
tops present mostly to the north of its low-level center. The 
initial intensity remains 45 kt for this advisory, based on 
overnight ASCAT data and the lack of noticeable change in 
Henriette's structure since that time.

Virtually no change was made to the NHC track forecast. Henriette 
is moving westward to west-northwestward to the south of a deep 
ridge centered over the northern east Pacific. In a few days, a 
trough approaching from the west will turn Henriette toward the 
northwest, taking the tropical cyclone north of Hawaii. The 
various deterministic and global ensemble models are all in good 
agreement on the forecast, so confidence in the track forecast is 
fairly high.

The tropical storm is still forecast to slowly weaken during the 
next few days while it moves over cool SSTs near 24C. However, once 
Henriette moves north of Hawaii, it will move over warmer waters. 
Upper-level difluent flow associated with a mid-latitude trough to 
the northwest may also provide additional support for 
intensification. As a result, most of the dynamical models forecast 
strengthening to occur near the end of the forecast period, and the 
NHC intensity forecast has been adjusted upward accordingly. Some of 
the guidance is much higher, including both HAFS models, which show 
Henriette developing a robust inner core by 120 h. Additional 
adjustments to the intensity forecast at day 4 or 5 may be needed 
with future advisories.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  06/1500Z 18.1N 129.7W   45 KT  50 MPH
 12H  07/0000Z 18.3N 132.0W   45 KT  50 MPH
 24H  07/1200Z 18.6N 135.0W   40 KT  45 MPH
 36H  08/0000Z 19.0N 138.0W   40 KT  45 MPH
 48H  08/1200Z 19.6N 141.1W   40 KT  45 MPH
 60H  09/0000Z 20.4N 144.0W   40 KT  45 MPH
 72H  09/1200Z 21.5N 146.6W   40 KT  45 MPH
 96H  10/1200Z 24.2N 151.3W   45 KT  50 MPH
120H  11/1200Z 27.5N 155.0W   60 KT  70 MPH
 
$$
Forecaster D. Zelinsky