{"id": "1213821639196311559", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-27T09:00:00Z", "msg": "180\nWTPZ43 KNHC 270855\nTCDEP3\n \nTropical Depression Eighteen-E Discussion Number   1\nNWS National Hurricane Center Miami FL       EP182026\n300 AM CST Sun Sep 27 2026\n\nThe tropical disturbance located south of Mexico, formerly Invest \n90E, has become better organized based on satellite imagery over the \nlast several hours. Scatterometry data from around 0300 UTC depicts \na closed circulation, with the system moving into a favorable \nenvironment for further development. Subjective Dvorak \nintensity analysis from TAFB also rated the system at 2.0/30 kt.  \nTherefore, advisories have begun for Tropical Depression \nEighteen-E. \n\nThe initial motion is somewhat uncertain since the cyclone has only \nrecently formed, but the motion estimate is around 285/9 kt. Track \nguidance is in good agreement on steering this system generally to \nthe west-northwest over the next several days, with an increase in \nforward speed as it runs south of a mid-level high over Mexico. The \ncurrent NHC track forecast generally falls within the middle of the \nguidance envelope, favoring HCCA in particular. \n\nSHIPS guidance suggests that vertical wind shear may be an \ninhibiting factor for development for the first 24 h, before the \nDepression is expected to gradually strengthen as SSTs remain warm \nand mid-level moisture appears favorable. There is some uncertainty \nwith regards to SSTs due to colder waters potentially being churned \nup in the wake of Hurricane Polo, so the current intensity forecast \nis a little conservative at first, before depicting gradual \nstrengthening through the late weekend onward. This still falls \naround the median of the guidance envelope. \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  27/0900Z 12.2N  99.1W   30 KT  35 MPH\n 12H  27/1800Z 12.7N  99.6W   30 KT  35 MPH\n 24H  28/0600Z 13.2N 100.8W   35 KT  40 MPH\n 36H  28/1800Z 13.8N 102.2W   45 KT  50 MPH\n 48H  29/0600Z 14.7N 104.1W   55 KT  65 MPH\n 60H  29/1800Z 15.7N 105.9W   65 KT  75 MPH\n 72H  30/0600Z 16.9N 107.7W   75 KT  85 MPH\n 96H  01/0600Z 18.7N 109.6W   80 KT  90 MPH\n120H  02/0600Z 19.7N 110.3W   75 KT  85 MPH\n \n"}