{"id": "1221675970162688002", "title": "Tropical Cyclone Discussion", "adv_date": "2026-10-25T03:00:00Z", "msg": "301\nWTPZ42 KNHC 250245\nTCDEP2\n \nHurricane Vance Discussion Number  15\nNWS National Hurricane Center Miami FL       EP222026\n900 PM CST Sat Oct 24 2026\n \nVance continues to look disorganized on satellite images, and it \nseems that southwesterly shear is keeping the convection displaced \nfrom the center. The hurricane is also moving over cool waters, \nwhich is also inhibiting intensification as well. GPM microwave \nimages show that the structure of the cyclone is vertically tilted \ndue to the aforementioned shear. Despite the system's ragged \nappearance, the Dvorak intensity estimate from TAFB is still \nT5.0/90 kt while the objective intensity estimates are in the range \nof 68-81 kt. Therefore, the initial intensity has been kept to 80 kt \nbased on a combination of that data, however, it could be generous. \n \nThe intensity forecast still has plenty of uncertainties. Vance is \ngenerally expected to weaken during the next 12 h due to the \ncontinuous of shear while it remains over cool SSTs. After that \ntime, the hurricane's intensity could fluctuate when Vance moves \nover warmer waters, but the wind shear will likely remain elevated. \nAfter 48 h, the wind shear is expected to increase even further and \nthat should result in a gradual weakening trend. It is possible \nthat Vance could weaken more than forecast given the expected \nincreasing shear and intrusions of dry air. The NHC intensity \nforecast is generally similar to the previous one with only a few \nminor adjustments made. \n \nThe initial motion remains slowly north-northwestward or 340/4 kt. \nThe cyclone is currently being steered by a weak low- to mid-level \nridge over eastern Mexico, and it is moving toward a large \nmid-latitude trough over the western United States and northwestern \nMexico. Vance should move into an area where the steering currents \nare light, thus the hurricane is expected to move even slower over \nthe next few days. The latest guidance shifted significantly to the \nwest compared to the previous forecast, including the highly skilled \nforecast aids HCCA and GDMI, which has added some uncertainty in the \ntrack forecast. The new track forecast was adjusted slightly to the \nwest and is a little slower than the previous one. However, the \ncurrent track is on the eastern side of the guidance envelope, and \nadditional adjustments to the west could be needed. \n \nKey Messages:\n \n1. Due to the uncertainties in both the track and intensity\nforecasts, it is too early to say what wind and storm surge\nimpacts Vance may cause along the coast of Mexico. Interests in\nsouthwestern Mexico should continue to monitor the progress of the\nhurricane.\n \n2. Heavy rainfall associated with slow-moving Hurricane Vance will\nimpact the western coast of Mexico from Michoac\u00e1n to Jalisco during\nmuch of next week. This rainfall may produce life-threatening\nflooding and mudslides across Colima and western portions of\nMichoac\u00e1n and Jalisco, especially in areas along steep terrain.\n \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  25/0300Z 13.7N 103.4W   80 KT  90 MPH\n 12H  25/1200Z 14.2N 103.7W   70 KT  80 MPH\n 24H  26/0000Z 15.1N 104.2W   70 KT  80 MPH\n 36H  26/1200Z 15.6N 104.6W   70 KT  80 MPH\n 48H  27/0000Z 16.1N 104.8W   70 KT  80 MPH\n 60H  27/1200Z 16.5N 105.0W   65 KT  75 MPH\n 72H  28/0000Z 17.3N 105.2W   55 KT  65 MPH\n 96H  29/0000Z 18.4N 105.6W   45 KT  50 MPH\n120H  30/0000Z 19.6N 106.1W   35 KT  40 MPH\n \n"}