Tropical Storm Lala Forecast Discussion
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Español: Aviso Publico Discusión |
961 WTPA42 PHFO 180249 TCDCP2 Tropical Storm Lala Discussion Number 23 NWS Central Pacific Hurricane Center Honolulu HI CP012026 Issued by NWS National Hurricane Center Miami FL 500 PM HST Mon Aug 17 2026 The visible and infrared satellite presentation of Lala has improved over the past several hours, with convection becoming increasingly organized around the center of the storm. A recent AMSR-2 microwave pass revealed a well-defined core with a convective band wrapping completely around the center. However, some westerly shear is evident, with the mid-level center displaced slightly to the east of the low-level center. Objective Dvorak intensity estimates from UW-CIMSS span a wide range of 41-63 kt, though these estimates have steadily increased over the past several hours. Subjective Dvorak intensity estimates from JTWC and WFO HFO were 3.5/55 kt and 4.0/65 kt, respectively. Given the improved satellite presentation and the upward trend in intensity estimates, the initial intensity is set at 60 kt for this advisory. The tropical storm is moving westward at around 10 kt, steered by a ridge of high pressure to the north, and this general motion is expected to continue through Tuesday. By midweek, an upper-level trough is forecast to approach the storm from the northwest, inducing a turn toward the northwest then north. This forecast brings Lala toward portions of the Papahanaumokuakea Marine National Monument on Thursday and Thursday night, and watches may be required for parts of that area on Tuesday. The latest NHC track forecast is very close to the previous forecast through 96 h, after which it has been accelerated, and remains near the middle of the track forecast consensus. Despite a relatively dry mid-level environment and moderate westerly wind shear, warm sea surface temperature and a well-established inner core are allowing for Lala to strengthen. All available model guidance support additional strengthening over the next 36 h, with the hurricane regional models and Google DeepMind (GDM) showing the most aggressive intensification. In addition, the ECMWF- and GFS-based SHIPS guidance indicate that rapid intensification is possible during this period. The forecast peak intensity has therefore been raised to 80 kt, which lies between the stronger regional hurricane models and GDM solution and the weaker statistical-dynamical model guidance. The longer-range intensity forecast remains more uncertain, as the global models suggest some potential for positive interaction with an upper-level trough later this week, followed by slow weakening as strong southwesterly shear develops. FORECAST POSITIONS AND MAX WINDS INIT 18/0300Z 20.3N 165.5W 60 KT 70 MPH 12H 18/1200Z 20.4N 166.9W 70 KT 80 MPH 24H 19/0000Z 20.6N 168.5W 75 KT 85 MPH 36H 19/1200Z 21.3N 170.0W 80 KT 90 MPH 48H 20/0000Z 22.3N 171.2W 80 KT 90 MPH 60H 20/1200Z 23.5N 172.1W 75 KT 85 MPH 72H 21/0000Z 24.8N 172.2W 75 KT 85 MPH 96H 22/0000Z 27.7N 171.1W 75 KT 85 MPH 120H 23/0000Z 31.3N 170.8W 70 KT 80 MPH $$ Forecaster Adams/Pasch