{"id": "1213041928057192455", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-24T15:00:00Z", "msg": "780\nWTPA42 PHFO 241450\nTCDCP2\n \nTropical Storm Nolo Discussion Number  16\nNWS Central Pacific Hurricane Center Honolulu HI   EP152026\nIssued by NWS National Hurricane Center Miami FL\n500 AM HST Thu Sep 24 2026\n\nSatellite images indicate that Nolo is gradually becoming better\norganized, with very deep convection in a curved band on the\nsouthern and western side of the circulation.  Additionally, a GPM\npass from overnight indicated that an inner core is forming,\nalthough the eastern side is fragmented.  Intensity estimates are\nrising, and the current wind speed is set to 50 kt as a blend of\nthe lower subjective and higher objective values.\n \nNolo has not moved much during the last several hours but should\nbegin to move northward and north-northeastward later today due to\na mid-latitude trough dropping over the northwestern Hawaiian\nIslands.  The trough is forecast to move westward by Saturday with\na building ridge north of the main Hawaiian Islands, causing a\nsharp westward turn this weekend.  The big question is how close\ndoes Nolo get before making that turn, with notable run-to-run\ninconsistencies in much of the guidance.  Similar to the last\ncycle, the bulk of the models have shifted slightly northward, and\nthe new NHC forecast is moved in that direction.  This remains a \nmore uncertain forecast than normal given the large unresolved\nnorth-south spread, with other possible complicating terrain \ninfluences of the Big Island (like we saw with Hurricane Lala last \nmonth).  Therefore, the long-range portion of the forecast is \nessentially unchanged.\n \nWith the formation of an inner core, conditions appear to be coming\ntogether for rapid intensification given the other conducive\nenvironmental factors of warm SSTs, low shear and high mid-level\nmoisture.  Nolo is likely to become a hurricane by tonight and \nreach major hurricane strength as it nears the Big Island on \nSaturday.  The new forecast is raised from the previous one, just \nbelow the HCCA aid, which has done well this year in these \nstrengthening episodes.  Note that a track closer to the Big Island \ncould substantially increase the threat of damaging winds, \nparticularly over higher terrain, along exposed ridges, and in areas \ndownwind of the ridges.\n \nKey Messages:\n\n1. Nolo is expected to strengthen into a hurricane today as it \nmoves northward to north-northeastward, potentially making its \nclosest approach to the Big Island of Hawaii as a major hurricane on \nSaturday. A Hurricane Watch remains in effect for the Big Island, \nand residents there should follow advice given by local officials, \nincluding evacuating if told to do so. A Hurricane Warning will \nlikely be required for the Big Island later today.\n\n2. The time to finish preparations for significant heavy rain \nand flooding impacts on the Big Island is now as heavy rain \nincreases in both coverage and intensity today and Friday. Periods \nof heavy rain are expected to continue across the Big Island and \nMaui through the weekend. Life-threatening, catastrophic flooding \nand mudslides are possible, especially in areas of steep terrain \nacross the Big Island and Maui. Across the remainder of Hawaii, \nlesser rainfall totals are expected, with isolated flooding \npossible.  \n\n3. Large and damaging waves are possible along portions of the \nBig Island's coastline into the weekend.\n\n4. Interests elsewhere in Hawaii should closely monitor the \nlatest forecast updates and ensure that they have their preparedness \nplans in place. Tropical Storm Watches may be required for other \nislands later today or on Friday.\n\n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  24/1500Z 14.9N 156.2W   50 KT  60 MPH\n 12H  25/0000Z 15.2N 156.2W   65 KT  75 MPH\n 24H  25/1200Z 16.1N 155.8W   80 KT  90 MPH\n 36H  26/0000Z 17.1N 155.4W   95 KT 110 MPH\n 48H  26/1200Z 17.8N 155.4W  100 KT 115 MPH\n 60H  27/0000Z 18.0N 156.4W  105 KT 120 MPH\n 72H  27/1200Z 18.1N 158.2W  105 KT 120 MPH\n 96H  28/1200Z 19.0N 162.0W  105 KT 120 MPH\n120H  29/1200Z 21.6N 164.4W   90 KT 105 MPH\n \n"}