{"id": "1213113909652946951", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-24T21:00:00Z", "msg": "961\nWTPA42 PHFO 242056\nTCDCP2\n \nTropical Storm Nolo Discussion Number  17\nNWS Central Pacific Hurricane Center Honolulu HI   EP152026\nIssued by NWS National Hurricane Center Miami FL\n1100 AM HST Thu Sep 24 2026\n \nNolo continues to become better organized, with a ragged eye on \nsatellite imagery and a primitive eyewall noted on the latest \nmicrowave pass.  The initial intensity is set to 60 kt, at the high \nend of the various estimates due to the improved organization on \nconventional satellite and microwave imagery.  An Air Force Reserve \nHurricane Hunter aircraft is scheduled to be in the storm this \nafternoon for a more precise estimate.\n \nThe storm has been moving erratically during the day, but appears to \nfinally be moving slowly northward.  There is no change the synoptic \nreasoning with a mid-latitude trough near the northwestern Hawaiian \nIslands causing Nolo to accelerate north-northeastward during the \nnext day or so.  The trough should move away by the weekend and be \nreplaced by a ridge, forcing a sharp westward turn on Saturday.  \nThe northward trend during the last couple of model cycles has \nstopped and is actually trending southward, led by the ECMWF model.  \nThe new forecast is a touch south of the last one, but really all \nthese track changes are quite small.  This remains an uncertain \nforecast with some model ensemble tracks still over the Big Island, \nthough most are south.  This forecast necessitates a Tropical Storm \nWarning for the Big Island, and a closer track could substantially \nincrease the threat of damaging winds, particularly over higher \nterrain, along exposed ridges, and in areas downwind of the ridges.\n\nRapid intensification is expected during the next day or so now \nthat an inner core has formed, combined with warm warm SSTs, low \nshear and high mid-level moisture.  Nolo is likely to become a \nhurricane by tonight and reach major hurricane strength as it nears \nthe Big Island on Saturday.  The new forecast is similar to the \nprevious one for the first few days, close to the HCCA aid.  At long \nrange, vertical wind shear is forecast to cause Nolo to weaken, and \nthe NHC intensity prediction is lowered at that time. \n \nKey Messages:\n\n1. Nolo is expected to pass near or just south of the Big Island of \nHawaii on Saturday as a major hurricane.  Tropical storm conditions \nare expected to begin on the Big Island Friday night with \nhurricane conditions possible on Saturday, particularly in areas of \nsteep terrain.  Residents should follow advice given by local \nofficials, including evacuating if told to do so. \n\n2. The time to finish preparations for significant heavy rain and \nflooding impacts on the Big Island is now as heavy rain increases in \nboth coverage and intensity today and Friday. Periods of heavy rain \nare expected to continue across the Big Island and Maui through the \nweekend. Life-threatening, catastrophic flooding and mudslides are \npossible, especially in areas of steep terrain across the Big Island \nand Maui. Across the remainder of Hawaii, lesser rainfall totals are \nexpected, with isolated flooding possible.  \n\n3. Large and damaging waves are likely along portions of the \nBig Island's coastline into the weekend.\n\n4. A Tropical Storm Watch is in effect for Maui County where \ntropical storm conditions are possible beginning on Saturday.  \nInterests elsewhere in Hawaii should closely monitor the latest \nforecast updates and ensure that they have their preparedness plans \nin place. \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  24/2100Z 14.9N 156.1W   60 KT  70 MPH\n 12H  25/0600Z 15.4N 156.0W   70 KT  80 MPH\n 24H  25/1800Z 16.4N 155.6W   85 KT 100 MPH\n 36H  26/0600Z 17.2N 155.5W   95 KT 110 MPH\n 48H  26/1800Z 17.7N 156.0W  100 KT 115 MPH\n 60H  27/0600Z 17.8N 157.3W  105 KT 120 MPH\n 72H  27/1800Z 17.8N 159.2W  105 KT 120 MPH\n 96H  28/1800Z 19.5N 163.0W   95 KT 110 MPH\n120H  29/1800Z 22.5N 165.2W   80 KT  90 MPH\n \n"}