{"id": "1206248874475651075", "title": "Tropical Cyclone Discussion", "adv_date": "2026-08-31T15:00:00Z", "msg": "809\nWTPA44 PHFO 311458\nTCDCP4\n \nTropical Storm Lowell Discussion Number  16\nNWS Central Pacific Hurricane Center Honolulu HI   EP122026\nIssued by NWS National Hurricane Center Miami FL\n500 AM HST Mon Aug 31 2026\n\nLowell consists of a large central dense overcast with very cold \ncloud tops.  A 31/1047 UTC AMSR2 pass indicates the low-level center \nis rapidly becoming better organized underneath the convective \ncanopy.  The latest subjective Dvorak estimates from PHFO and JTWC \nrange from 45-55 kt, and objective estimates are a bit lower than \nthe subjective estimates.  The initial intensity is raised to 55 kt \nbased on the improved structure noted on the AMSR2 pass.\n \nThe initial motion is just south of due west, or 260 degrees at 12 \nkt.  A mid-level ridge north of Lowell will be the primary steering \nmechanism for the next few days.  Lowell should move generally \nwestward to west-northwestward during that time.  Thereafter, model \nspread increases as Lowell slows.  A west-northwestward motion is \nforecast after day 4 as Lowell feels some pull from a mid- to \nupper-level trough located well to its north.  The HCCA and Google \nDeepMind ensemble (GDMI) are the fastest and farthest south models. \nThe latest NHC forecast track is slightly to the left of the \nprevious track, but not quite as far south as the GDMI.\n \nThe moderate easterly shear that has been affecting Lowell appears \nto be diminishing.  Lowell seems poised to take advantage of warm \nwaters to rapidly intensify, as shown by the HAFS-A and HAF-B \nmodels, which forecast Lowell becoming a major hurricane within the \nnext 36 h.  SHIPS is forecasting weak vertical wind shear magnitudes \nover the next 5 days.  Given that the cyclone has developed a closed \nring on 37 GHz microwave imagery, it is probably just a matter of \ntime before we see Lowell strengthen significantly. The new NHC \nintensity forecast explicitly forecasts rapid intensification over \nthe next 36 h, and then holds Lowell at category 3 strength through \nthe day 5 period, since SSTs are forecast to still be between 28-29C \nand the shear is still forecast to be light at day 5.  The new \nintensity forecast is between the middle and higher end of the \nintensity guidance envelope.  This forecast is slightly above the \nintensity consensus, but not nearly as strong as the HCCA.\n\n \nKey Messages:\n \n1. Lowell is forecast to move generally westward and could be in the\nvicinity of the Hawaiian Islands late this week. Interests in Hawaii\nshould monitor the progress of this storm.\n \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  31/1500Z 12.8N 145.7W   55 KT  65 MPH\n 12H  01/0000Z 12.9N 147.1W   65 KT  75 MPH\n 24H  01/1200Z 13.1N 149.0W   80 KT  90 MPH\n 36H  02/0000Z 13.4N 150.9W   95 KT 110 MPH\n 48H  02/1200Z 13.6N 152.7W  100 KT 115 MPH\n 60H  03/0000Z 14.0N 154.7W  105 KT 120 MPH\n 72H  03/1200Z 14.4N 156.5W  105 KT 120 MPH\n 96H  04/1200Z 14.9N 159.4W  105 KT 120 MPH\n120H  05/1200Z 15.4N 161.7W  105 KT 120 MPH\n \n"}