{"id": "1212757692999139335", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-23T15:00:00Z", "msg": "211\nWTPZ42 KNHC 231444\nTCDEP2\n \nHurricane Polo Discussion Number  12\nNWS National Hurricane Center Miami FL       EP172026\n900 AM CST Wed Sep 23 2026\n\nSatellite imagery this morning indicates that Polo is continuing to \nundergo an eyewall replacement cycle, with infrared imagery showing \nmultiple rings of cold tops near and around the center. Overall, \nthe hurricane is not as intense as it was 24 h ago, as the eye has \nbecome less distinct and the eyewall cloud tops have warmed. The \nvarious satellite intensity estimates have trended downward, and \nbased on this trend the initial intensity is lowered to a possibly \ngenerous 130 kt.  Outer rainbands in the northeastern semicircle \nhave reached the coast of Mexico.\n\nPolo is starting its forecast turn toward the northwest with the \ninitial motion now 325/4 kt.  Water vapor imagery suggests a \nmid-level ridge is building over Texas and Mexico, and the \ndynamical models forecast this ridge to build westward to the north \nof Polo for the next 2-3 days. This evolution should result in Polo \nmoving northwestward and then west-northwestward with some increase \nin forward speed. The forecast becomes more uncertain after 60-72 \nh. The dynamical models forecast the ridge to the north to weaken\naround that time as a mid-latitude trough moves into the western \nUnited States. There is also the possibility of interaction with \nHurricane Odalys to the west. The guidance becomes divergent by \n120 h, with the GFS/HCCA/Google DeepMind/Florida State \nSuperensemble showing a northward motion close to Baja California, \nwhile the regional hurricane models/UKMET/Canadian show a \nnorthwestward motion farther away from Baja.  The track forecast \ngoes with the northward motion scenario, but there is a significant \namount of uncertainty in this portion of the forecast.\n\nThe trends of the intensity forecast guidance suggest that Polo \ncould weaken a little during the next day or so, followed by \nre-intensification during the ensuing 24 h. The first two days of \nthe intensity forecast follow these trends, and there could be \nfluctuations in intensity due to eyewall replacement cycles \nsuperimposed on top of this overall trend. After 48 h, the \nenvironment gradually becomes less favorable due to slightly \nstronger shear and the possibility of some dry air entrainment. The \nguidance forecast slow weakening during this time, and the new \nintensity forecast follows suit. The new forecast is near the upper \nedge of the guidance for the first 60 h and then lies closer to the \nmiddle of the guidance envelope.\n\nWhile the center of Polo is forecast to remain offshore, outer \nrainbands should spread across southwestern Mexico during the next \nday or so, producing areas of heavy rain and tropical-storm-force \nwinds.\n \nKey Messages:\n \n1. Heavy rainfall associated with Polo will impact coastal portions \nof southwest Mexico through Thursday. This rainfall may produce \nlife-threatening flooding and mudslides, especially in areas of \nsteep terrain.\n \n2. A Tropical Storm Warning is in effect for portions of\nsouthwestern Mexico, and a Tropical Storm Watch is in effect\nwestward to Playa Perula. Interests in these areas should closely\nmonitor updates to the forecast.\n \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  23/1500Z 15.4N 101.8W  130 KT 150 MPH\n 12H  24/0000Z 15.9N 102.5W  125 KT 145 MPH\n 24H  24/1200Z 16.5N 104.0W  125 KT 145 MPH\n 36H  25/0000Z 16.8N 105.8W  130 KT 150 MPH\n 48H  25/1200Z 17.0N 107.7W  130 KT 150 MPH\n 60H  26/0000Z 17.2N 109.6W  125 KT 145 MPH\n 72H  26/1200Z 18.0N 111.1W  120 KT 140 MPH\n 96H  27/1200Z 20.7N 112.9W  105 KT 120 MPH\n120H  28/1200Z 23.2N 113.1W   90 KT 105 MPH\n \n"}