{"id": "1218776120951963651", "title": "Tropical Cyclone Discussion", "adv_date": "2026-10-14T21:00:00Z", "msg": "337\nWTPZ45 KNHC 142055\nTCDEP5\n \nHurricane Simon Discussion Number  30\nNWS National Hurricane Center Miami FL       EP202026\n200 PM MST Wed Oct 14 2026\n\nSimon is showing how small tropical cyclones can undergo rapid \nweakening as well as rapid intensification. A synthetic aperture \nradar (SAR) overpass near 13Z showed winds in the eyewall of 65-75 \nkt, suggesting that the intensity in the previous advisory was too \nhigh. An Air Force Reserve Hurricane Hunter aircraft has just \nreported that the storm is now weaker, with no hurricane-force \nwinds present so far at 700 mb. The central pressure is near 989 mb \nbased on a dropsonde with a surface pressure of 993 mb and surface \nwinds of 41 kt. The initial intensity is reduced to 65 kt based \nmainly on the central pressure, and it is likely that this is \ngenerous. The aircraft reported a 16-nm wide eye open to the \nsouthwest and a larger radius of maximum wind than shown by the \nearlier SAR data.\n \nThe hurricane continues drifting southwest or 235/3 kt. For the\nnext day or so, Simon should continue drifting southwestward or \nsouthward in an area of light steering currents, with the center \nremaining well offshore. After that time, there remains some \nspread in the track guidance models. While all of the global models\nagree that a mid- to upper-level trough should form west of Baja\nCalifornia near and after 48 h, there remains disagreement on how \nthis will affect Simon's track. The HAFS models keep the cyclone\nmoving southward through 72 h, while the GFS model does not show\nany northward turn until 48 h. The remainder of the guidance\nforecasts a turn toward the northwest or north-northwest around 36\nh, with that motion continuing through the end of the forecast\nperiod. The new track forecast follows the latter scenario in\nanticipation that the center will try to follow convective bursts\ndisplaced to the north by southerly shear. Overall, the track\nguidance envelope has shifted westward since the previous advisory,\nand so has the track forecast.\n \nSimon is currently experiencing light to moderate northerly shear \nand dry air entrainment, and this combination has at least \ntemporarily disrupted the eyewall convection. The shear is likely \nto subside during the next 6-18 h, and based on this the intensity \nforecast keeps the cyclone as a minimal hurricane.  After 36 h, \nincreasing southerly and southwesterly upper-level winds between \nthe trough to the northwest and Tropical Storm Trudy to the \nsoutheast should cause significant shear over Simon. The intensity \nforecast shows steady weakening during this time, and there is a \npossibility that Simon could weaken faster and dissipate sooner than \ncurrently forecast.\n\n \nKey Messages:\n \n1. Interests in Baja California Sur should continue to closely\nmonitor the latest updates. Watches or warnings could be required\nfor portions of Baja California Sur over the next day or two.\n \n2. Large swells will likely affect portions of the coast of\nwest-central Mexico and Baja California Sur over the next several\ndays. These swells could cause life-threatening surf and rip current\nconditions.\n \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  14/2100Z 19.3N 108.3W   65 KT  75 MPH\n 12H  15/0600Z 19.2N 108.5W   65 KT  75 MPH\n 24H  15/1800Z 19.1N 108.4W   65 KT  75 MPH\n 36H  16/0600Z 19.5N 108.6W   65 KT  75 MPH\n 48H  16/1800Z 20.3N 109.5W   60 KT  70 MPH\n 60H  17/0600Z 21.5N 110.5W   55 KT  65 MPH\n 72H  17/1800Z 22.8N 111.5W   45 KT  50 MPH\n 96H  18/1800Z 24.9N 113.2W   30 KT  35 MPH\n120H  19/1800Z 26.7N 114.2W   25 KT  30 MPH...POST-TROP/REMNT LOW\n \n"}