{"id": "1212476690322096135", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-22T15:00:00Z", "msg": "384\nWTPZ42 KNHC 221455\nTCDEP2\n \nHurricane Polo Discussion Number   8\nNWS National Hurricane Center Miami FL       EP172026\n900 AM CST Tue Sep 22 2026\n\nPolo has a spectacular presentation on geostationary and microwave \nsatellite imagery, with a small well-defined eye surrounded by a \nsymmetrical area of very deep convection.  The upper-level outflow \nis quite prominent over all quadrants of the system and there are \nstrong convective banding features surrounding the central dense \novercast.  A Subjective Dvorak data T-number from TAFB just after \n1200 UTC was 7.0, corresponding to 140 kt, and assuming a little \nmore strengthening since that time, the advisory intensity is set \nto 145 kt. Despite its great strength, Polo remains a relatively\nsmall cyclone with its hurricane and tropical-storm-force winds\nestimated to only extend about 30 and 80 n mi from the eye,\nrespectively.\n \nThe powerful hurricane appears to have stopped moving eastward, and \nit is now drifting northward at around 360/2 kt.  A deep-layer \nridge is becoming established over Mexico.  This evolution of the \nsteering pattern should result in Polo turning west-northwestward \nand beginning to move parallel, but fairly close to, the coast of \nMexico over the next couple of days.  There is still uncertainty as \nto how close the hurricane will get to the coast, and some wind, \nrain, and surf impacts appear likely when Polo makes its closest \napproach.  A Tropical Storm Warning has been issued for a portion \nof the coast of Mexico and the Tropical Storm Watch has been \nextended westward.  Polo should begin to pull away from southwestern \nMexico Thursday night and Friday as the ridge keeps the system on a \nwest-northwestward to northwestward path.  The steering currents \nbecome more uncertain over the weekend when Polo reaches the western \nedge of the ridge and nears Tropical Storm Odalys to its west. \nHowever Polo is likely to slow down and move more northward around \nday 5.  Little change was made to the NHC track forecast, which lies \non the northern side of the guidance envelope.\n \nPolo should remain in an environment that is very  conducive for \nstrengthening during next couple of days.  It should be noted that \nfor these intense hurricanes, inner-core changes such as eyewall \nreplacements are quite common.  These changes can lead to some \nfluctuations in intensity.  However, Polo is likely to remain a \ndangerous major hurricane through the forecast period.\n\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 now in effect for portions of \nsouthwestern Mexico, and the Tropical Storm Watch has been extended \nwestward along the coast.  Interests in these areas should closely \nmonitor updates to the forecast.\n  \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  22/1500Z 14.7N 101.6W  145 KT 165 MPH\n 12H  23/0000Z 15.0N 101.5W  155 KT 180 MPH\n 24H  23/1200Z 15.4N 101.9W  150 KT 175 MPH\n 36H  24/0000Z 16.1N 102.8W  150 KT 175 MPH\n 48H  24/1200Z 16.7N 104.2W  140 KT 160 MPH\n 60H  25/0000Z 17.1N 105.9W  130 KT 150 MPH\n 72H  25/1200Z 17.3N 107.5W  125 KT 145 MPH\n 96H  26/1200Z 18.4N 110.8W  115 KT 130 MPH\n120H  27/1200Z 20.8N 112.7W  105 KT 120 MPH\n \n"}