{"id": "1213325111547658247", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-25T15:00:00Z", "msg": "109\nWTPZ42 KNHC 251450\nTCDEP2\n \nHurricane Polo Discussion Number  20\nNWS National Hurricane Center Miami FL       EP172026\n800 AM MST Fri Sep 25 2026\n \nAfter regaining Category 5 status overnight, the remarkable\nsatellite presentation of Polo indicates the hurricane has continued\nto intensify. The eye has contracted and warmed over the past\nseveral hours, with temperatures above 20 deg C measured inside the\neye. A thick, solid ring of deep convection surrounds the center,\nwith cloud tops as cold as -80 to -85 deg C. There were no\nindications of a concentric eyewall structure in 0905 UTC AMSR3\npassive microwave imagery. The latest UW-CIMSS ADT estimates and a\nT7.5 Dvorak classification from TAFB support an initial intensity of\n155 kt. A NOAA research aircraft mission is scheduled to investigate\nPolo later today.\n \nPolo continues moving westward (270/10 kt) along the south side of a\nmid-level ridge that extends across northern Mexico. This weekend, a\ndeep-layer trough approaching from the west is expected to erode the\nsteering ridge. This will cause Polo to turn northwestward and\nnorthward as it moves around the western side of the ridge. By\nMonday, the increasing influence of the upper trough should turn\nPolo northeastward toward Baja California Sur and west-central\nMexico. The global models and AI-based guidance are generally\nin good agreement on this track evolution. The updated NHC track\nforecast is adjusted slightly to the left of the previous one, and\nis also a bit slower to come into better agreement with the latest\nmulti-model consensus. Overall, the NHC forecast remains on the\nfaster and right side of the envelope, closer to HCCA and GDMI.\nBased on this prediction, watches could be required for portions of\nthe Baja California Peninsula as early as Saturday.\n \nBased on the aforementioned AMSR3 data, an eyewall replacement cycle\n(ERC) does not appear imminent. Thus, further slight strengthening\ncannot be ruled out while Polo remains over very warm waters in a\nweaker shear environment. The vertical wind shear is expected to\nincrease over the weekend, and because of this as well as the\npossibility of a future ERC, the NHC intensity forecast shows a\nweakening trend beginning on Saturday and continuing into next week.\nRegardless, Polo is predicted to approach Baja California Sur as a\nstrong hurricane early next week, and interests there should closely\nmonitor the latest forecast updates. The NHC forecast remains on the\nhigher side of the intensity guidance, generally following HCCA.\nOnce land interaction occurs with the Baja California Peninsula and\nmainland Mexico, more rapid weakening is anticipated.\n \nDistant moisture from Hurricane Polo and Odalys will be transported\ninto the southwestern United States this weekend and early next\nweek, and may indirectly contribute to a heavy rainfall and flash\nflood threat in the region. See products issued by the Weather\nPrediction Center for more information.\n \n \nKey Messages:\n \n1. Polo is forecast to approach the Baja California Peninsula early\nnext week as a hurricane. Interests there should closely monitor\nthe latest updates and ensure that they have their preparedness\nplan in place. Watches could be required as early as Saturday for\nportions of the area.\n \n2. Heavy rainfall associated with Polo may begin to impact Baja\nCalifornia Sur late Sunday into Monday. This rainfall may produce\nlife-threatening flooding and mudslides, especially in areas of\nsteep terrain.\n \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  25/1500Z 17.1N 108.5W  155 KT 180 MPH\n 12H  26/0000Z 17.2N 109.8W  155 KT 180 MPH\n 24H  26/1200Z 17.8N 111.5W  140 KT 160 MPH\n 36H  27/0000Z 18.9N 112.7W  125 KT 145 MPH\n 48H  27/1200Z 20.4N 113.4W  110 KT 125 MPH\n 60H  28/0000Z 22.0N 113.7W  100 KT 115 MPH\n 72H  28/1200Z 23.8N 113.4W   95 KT 110 MPH\n 96H  29/1200Z 26.9N 110.8W   70 KT  80 MPH\n120H  30/1200Z 30.4N 106.5W   30 KT  35 MPH...POST-TROP/INLAND\n \n"}