Tropical Storm Lala Forecast Discussion
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000 WTPA42 PHFO 170237 TCDCP2 Tropical Storm Lala Discussion Number 19 NWS Central Pacific Hurricane Center Honolulu HI CP012026 Issued by NWS National Hurricane Center Miami FL 500 PM HST Sun Aug 16 2026 Lala has shown very little change in convective structure over the past several hours as it begins to move away from the main Hawaiian Islands. Deep convection remains over the center of the circulation, with a large fragmented convective band wrapping into the center across the northern and western semicircles. The latest subjective Current Intensity estimates from HFO and JTWC are T3.5/55 kt, with objective intensity estimates ranging from 35 to 50 kt. Based on these data and the steady trend in satellite presentation, the initial intensity is held at a possibly generous 55 kt for this advisory. Lala is moving westward, or 265/14 kt. A strong subtropical ridge positioned north of the cyclone should maintain Lala on a generally westward motion through the first half of the week. Thereafter, a weakness is forecast to develop in the ridge in response to a shortwave trough moving across the northern Pacific, causing Lala to slow and gradually turn toward the northwest and then northward during the latter half of the week. Track forecast confidence remains relatively high through the first half of the week, but decreases thereafter due to run-to-run inconsistencies in the models and considerable cross-track spread among the guidance. The latest NHC track forecast is very close to or slightly left of the previous advisory through midweek, then follows a blend of the previous forecast, the multi-model consensus (HCCA), and the Google DeepMind ensemble mean thereafter to account for the increasing uncertainty. Little change in intensity is expected during the next day or two as Lala continues westward away from the main Hawaiian Islands and south of the eastern portion of the Northwestern Hawaiian Islands. Thereafter, the intensity guidance continues to indicate a strengthening trend, with Lala forecast to regain hurricane intensity around midweek as it begins to turn northwestward. Although the cyclone will remain over warm waters, mid-level dry air and increasing westerly vertical wind shear could limit the amount of strengthening that occurs later in the forecast period. Nevertheless, much of the guidance continues to show Lala strengthening as it approaches portions of the Northwestern Hawaiian Islands later in the week. The latest NHC intensity forecast is similar to the previous advisory through midweek, then trends toward the middle of the guidance envelope during the latter half of the forecast period. Key Messages: 1. Tropical-storm-force winds, especially in gusts, will persist over Kauai County into the overnight period. The strongest winds will occur over areas of higher terrain. 2. Rain will continue to taper off across the Big Island and Maui by tonight, however additional areas of flash flooding and mudslides will be possible. Heavy rainfall and the potential for flooding and mudslides from Lala will continue across the rest of the island chain through later tonight or early Monday. 3. Large waves generated by Lala will continue to impact exposed shores of the Hawaiian Islands through tonight, with a gradual downward trend expected from east to west by Monday. This heavy surf may cause localized coastal flooding and significant beach erosion. 4. Use caution after Lala passes as deadly hazards remain, including flooded areas and downed power lines. If you use a generator, be sure it is placed outside at least 20 feet away from doors, windows, and garages to avoid deadly carbon monoxide poisoning. FORECAST POSITIONS AND MAX WINDS INIT 17/0300Z 20.7N 161.6W 55 KT 65 MPH 12H 17/1200Z 20.8N 163.4W 50 KT 60 MPH 24H 18/0000Z 20.6N 165.3W 50 KT 60 MPH 36H 18/1200Z 20.6N 167.2W 55 KT 65 MPH 48H 19/0000Z 20.7N 168.9W 60 KT 70 MPH 60H 19/1200Z 21.1N 170.3W 65 KT 75 MPH 72H 20/0000Z 22.1N 171.8W 70 KT 80 MPH 96H 21/0000Z 23.9N 173.9W 70 KT 80 MPH 120H 22/0000Z 25.9N 173.6W 70 KT 80 MPH $$ Forecaster Gibbs/Evans