847 WTPZ43 KNHC 080253 TCDEP3 Tropical Storm Henriette Discussion Number 16 NWS National Hurricane Center Miami FL EP082025 500 PM HST Thu Aug 07 2025 Henriette’s satellite presentation has changed little since the previous advisory, with the low-level center remaining mostly exposed and only a few small, intermittent bursts of deep convection developing near the low-level center. The latest subjective Dvorak intensity estimate from TAFB was 2.5/35 kt, while objective estimates from UW-CIMSS have ranged from 28 to 41 kt over the past several hours. Taking a blend of these data, the initial intensity has been reduced to 35 kt for this advisory. Henriette is moving westward, or 280 degrees at 14 kt. A turn toward the west-northwest is expected tonight, with this general motion expected to persist over the next couple of days as the cyclone tracks along the southwestern periphery of a subtropical ridge to its north. A turn toward the northwest is forecast this weekend and into early next week as Henriette becomes steered between an amplifying longwave trough northwest of Hawaii and the subtropical ridge to its northeast. The official track forecast remains in close agreement with the latest multi-model consensus aids and is essentially unchanged from the previous advisory. Confidence remains high that Henriette will remain far to the north of Hawaii. Henriette will traverse sea surface temperatures near 24C with mid-level relative humidity below 50 percent during the next 24 to 36 hours. Despite these unfavorable thermodynamic conditions, the cyclone’s well-defined circulation is expected to remain fairly resilient within the prevailing low-shear environment, allowing for occasional pulses of deep convection to persist. As a result, little change in intensity is anticipated in the short term. If Henriette can withstand the period over cooler waters, as has been consistently indicated by the GFS and ECMWF models for several days now, re-intensification will likely occur over the weekend and into early next week as sea surface temperatures rise to levels conducive for strengthening. The official forecast continues to reflect intensification, bringing Henriette to hurricane strength by 96 hours. The intensity forecast is on the higher end of the guidance envelope, and is most closely aligned with the dynamical intensity consensus HCCA. FORECAST POSITIONS AND MAX WINDS INIT 08/0300Z 19.1N 138.4W 35 KT 40 MPH 12H 08/1200Z 19.6N 140.8W 35 KT 40 MPH 24H 09/0000Z 20.4N 143.8W 35 KT 40 MPH 36H 09/1200Z 21.6N 146.5W 35 KT 40 MPH 48H 10/0000Z 22.9N 149.0W 40 KT 45 MPH 60H 10/1200Z 24.4N 151.3W 50 KT 60 MPH 72H 11/0000Z 26.2N 153.6W 60 KT 70 MPH 96H 12/0000Z 30.2N 157.7W 70 KT 80 MPH 120H 13/0000Z 34.8N 161.8W 65 KT 75 MPH $$ Forecaster Jelsema (CPHC)
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