Issued at 500 AM HST Sat Aug 01 2026
000 WTPZ42 KNHC 011435 TCDEP2 Tropical Storm Genevieve Discussion Number 34 NWS National Hurricane Center Miami FL EP072026 500 AM HST Sat Aug 01 2026 Genevieve’s deep convection has been gradually decreasing over the past day or so, and there is now only a relatively small area of cloud tops colder than -30C, mainly in the northeast quadrant. However, a 1032 UTC AMSR-2 pass indicates that a relatively large area of shallow to moderate convection persists, and is wrapped halfway around the low-level center over the northeast semicircle. The subjective current intensity (CI) estimate from TAFB has decreased to 2.5/35 kt. The latest objective AiDT, D-PRINT, D-MINT and SATCON intensity estimates range from 37-42 kt. Given the latest intensity estimates, the initial intensity is brought down to 40 kt for this advisory. The initial motion estimate is west-northwestward, or 285/12 kt. This general motion will continue over the weekend as a low- to mid-level ridge remains north of the cyclone. By Monday, a gradual turn to the northwest and north-northwest is expected as the ridge weakens north of the cyclone due to a deep-layer low/trough that will be located off to the north-northwest of Genevieve. Very little change was made to the previous NHC track forecast, which lies close to the latest Google DeepMind Ensemble Mean. The track guidance remains tightly clustered through day 3, so there is high confidence in the track forecast. Genevieve has been traversing 25-26C sea-surface temperatures (SSTs), while under weak vertical wind shear and within a relatively dry, stable environment. The cyclone will move over progressively colder SSTs over the next 18 h or so (below 24C by that time). Southwesterly vertical wind shear will then increase to moderate levels (15-20 kt) in 24-36 h while the environment remains dry and stable. These conditions will lead to continued gradual weakening, and Genevieve is likely to lose its convection and become post-tropical in about 36 h. Thereafter, the remnant low should gradually spin down with dissipation occurring just after 96 h, as depicted by the global models. The latest NHC intensity forecast is similar to the previous advisory and lies near the middle of the guidance envelope. FORECAST POSITIONS AND MAX WINDS INIT 01/1500Z 23.0N 133.7W 40 KT 45 MPH 12H 02/0000Z 23.6N 135.7W 40 KT 45 MPH 24H 02/1200Z 24.5N 138.3W 35 KT 40 MPH 36H 03/0000Z 25.5N 140.8W 35 KT 40 MPH...POST-TROPICAL 48H 03/1200Z 26.4N 143.0W 35 KT 40 MPH...POST-TROPICAL 60H 04/0000Z 27.4N 144.4W 30 KT 35 MPH...POST-TROP/REMNT LOW 72H 04/1200Z 28.4N 145.4W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 05/1200Z 31.1N 146.2W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 06/1200Z...DISSIPATED $$ Forecaster Hagen
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