Tropical Storm Henriette Discussion Number 34

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Tropical Storm Henriette Discussion Number 34 NWS Central Pacific Hurricane Center Honolulu HI EP082025 Issued by NWS National Hurricane Center Miami FL 500 AM HST Tue Aug 12 2025 The overall satellite presentation of Henriette has not changed much overnight with deep convection over the small inner core of the cyclone. Earlier microwave imagery showed that the eye had become less distinct, and the latest subjective and objective satellite intensity estimates have begun to decrease. A blend of Dvorak Final-T and CI-numbers from the subjective estimates support an initial intensity of 60 kt for this advisory. Environmental conditions consisting of SSTs of 26-27 degrees C and moderate vertical wind shear suggests that only gradual weakening will occur today. However, the shear is forecast to increase significantly overnight and on Wednesday which should result in a faster rate of demise. Simulated satellite imagery from the global models show the system decoupling in 24 to 36 hours, and the updated forecast calls for Henriette to become post-tropical by 36 hours, but this could occur a little sooner. The latest NHC intensity forecast is near the IVCN multi-model consensus aid, which is a little above the HFIP corrected consensus that indicates an even faster rate of weakening. Henriette is moving northwestward or 315/15 kt, and this general motion should continue for another 24 to 36 hours as the system is steered between a mid-level ridge to its northeast and an upper-level low to the west. As the cyclone weakens and is steered more by the low-level low it is expected to decelerate and turn north-northwestward and northward. The updated official track forecast is essentially an update of the previous advisory and lies close to the various consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 12/1500Z 32.8N 161.6W 60 KT 70 MPH 12H 13/0000Z 34.3N 163.5W 55 KT 65 MPH 24H 13/1200Z 36.2N 166.0W 45 KT 50 MPH 36H 14/0000Z 38.3N 168.2W 35 KT 40 MPH...POST-TROPICAL 48H 14/1200Z 40.7N 169.7W 25 KT 30 MPH...POST-TROP/REMNT LOW 60H 15/0000Z 42.7N 169.7W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 15/1200Z...DISSIPATED