{"id": "1208863034448805890", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-09T21:00:00Z", "msg": "677\nWTPA44 PHFO 092035\nTCDCP4\n \nTropical Storm Lowell Discussion Number  55\nNWS Central Pacific Hurricane Center Honolulu HI   EP122026\nIssued by NWS National Hurricane Center Miami FL\n1100 AM HST Wed Sep 09 2026\n\nLowell is dealing with moderate wind shear and dry air. Recent \nsatellite imagery reveals that earlier deep convection has \ncollapsed, with only shallow convection remaining sheared to the \neastern side of the circulation. The latest subjective Dvorak \nintensity estimates from PHFO and JTWC have decreased to T2.5/35 kt, \nwhich is consistent with the system's degraded satellite \npresentation. UW-CIMSS objective intensity estimates currently range \nfrom 39 to 49 kt. Metop-B and Metop-C scatterometer passes are \nanticipated over Lowell near the advisory time, which will help \nbetter assess the current intensity and wind radii structure. \nAlthough current satellite estimates have decreased, the initial \nintensity is held at 50 kt for this advisory, which may be generous. \nSubsequent adjustments will await the incoming scatterometer wind \ndata.\n \nLowell is expected to remain within a dry environment with moderate \nvertical wind shear. Model-simulated infrared imagery suggests that \nLowell will continue to produce intermittent bursts of deep \nconvection over the next several days, aided by some upper-level \ndivergence in about 48 hours. The official NHC intensity forecast \nfollows the latest consensus model guidance, depicting a gradual \nweakening of the system throughout the forecast period. By the end \nof the period, the cyclone is forecast to move over cooler sea \nsurface temperatures while continuing to deal with dry air and \nmoderate shear. Although some uncertainty remains late in the period \ndue to the system's eventual track and intermittent convective \nbursts, these hostile environmental conditions should cause Lowell \nto become a post-tropical cyclone by day 4.  \n  \nThe initial motion is northwestward, or 320/12 kt. Lowell should \ngradually turn west-northwestward and then westward, steered by a \nbuilding mid-level ridge to the north and east. In a few days, the \ncyclone is forecast to round the western periphery of the ridge and \nslow forward speed. This decrease in forward speed will occur as the \nsteering pattern collapses, leaving Lowell caught between \nhigh-pressure ridges over the northwestern and northeastern Pacific. \nTrack model guidance begins to diverge considerably late in the \nperiod. This spread in the guidance largely depends on the vertical \ndepth of the cyclone, and if the system remains a shallow low, it \ncould begin to move southwestward, steered by the low-level flow on \nthe eastern edge of the northwestern Pacific ridge. The official NHC \ntrack forecast lies near the HCCA and GDMI consensus aids in the \nnear term, and then shifts toward the simple consensus later in the \nperiod, reflecting the higher uncertainty toward the end of the \nforecast cycle.\n \n \nKEY MESSAGES:\n \n1. Post-storm safety: Follow advice of local officials and avoid\nareas of downed power lines and flooding. Ensure generators are\nproperly ventilated and placed outside at least 20 feet away from\ndwellings and garages to avoid carbon monoxide poisoning. During\nclean up, be careful when using chainsaws and power tools. Drink\nplenty of water to avoid heat exhaustion.\n \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  09/2100Z 28.9N 163.7W   50 KT  60 MPH\n 12H  10/0600Z 29.3N 165.7W   45 KT  50 MPH\n 24H  10/1800Z 29.3N 168.1W   45 KT  50 MPH\n 36H  11/0600Z 29.3N 170.5W   40 KT  45 MPH\n 48H  11/1800Z 29.9N 171.7W   40 KT  45 MPH\n 60H  12/0600Z 30.9N 171.8W   40 KT  45 MPH\n 72H  12/1800Z 32.3N 172.3W   40 KT  45 MPH\n 96H  13/1800Z 33.2N 174.8W   35 KT  40 MPH...POST-TROPICAL\n120H  14/1800Z 32.7N 176.0W   30 KT  35 MPH...POST-TROP/REMNT LOW\n \n"}