000 WTPZ43 KNHC 062054 TCDEP3 Tropical Storm Henriette Discussion Number 11 NWS National Hurricane Center Miami FL EP082025 1100 AM HST Wed Aug 06 2025 Henriette continues along with little change in its structure. Like 6 h ago, it is producing a relatively small area of deep convection, with cold cloud tops present mostly to the north of its low-level center. Recent scatterometer data showed winds just above 40 kt, which supports maintaining the intensity at 45 kt for this advisory, after accounting for undersampling. The scatterometer data was also helpful with identifying the exact position of Henriette's center, which was slightly south of previous estimates. No significant change was made to the NHC track forecast outside a slight southward adjustment based on the initial position estimate in the short term. 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 reflects this and is very similar to the previous advisory. FORECAST POSITIONS AND MAX WINDS INIT 06/2100Z 18.1N 131.3W 45 KT 50 MPH 12H 07/0600Z 18.3N 133.5W 45 KT 50 MPH 24H 07/1800Z 18.6N 136.5W 40 KT 45 MPH 36H 08/0600Z 19.0N 139.5W 40 KT 45 MPH 48H 08/1800Z 19.7N 142.5W 40 KT 45 MPH 60H 09/0600Z 20.7N 145.2W 40 KT 45 MPH 72H 09/1800Z 22.0N 147.8W 40 KT 45 MPH 96H 10/1800Z 24.9N 152.0W 50 KT 60 MPH 120H 11/1800Z 28.5N 156.0W 60 KT 70 MPH $$ Forecaster Santos/D. Zelinsky
Source link