{"id": "1211838367387713543", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-20T09:00:00Z", "msg": "608\nWTPZ41 KNHC 200848\nTCDEP1\n \nTropical Storm Odalys Discussion Number   1\nNWS National Hurricane Center Miami FL       EP162026\n200 AM PDT Sun Sep 20 2026\n \nSatellite imagery indicates that the convective organization of \nOdalys has improved over the past several hours. Deep convection \ncontinues to develop within a band wrapping around the western and \nsouthern semicircles, with a recent burst of convection expanding \nover or near the circulation center. The latest subjective Dvorak \nintensity estimate from TAFB is T2.5/35 kt. Given these data and the \nimproved satellite presentation, advisories are being initiated on \nnewly formed Tropical Storm Odalys, with an initial intensity of 35 \nkt.\n\nThe initial motion is estimated to be northwestward, or 305/7 kt. \nThis general motion is expected to continue during the next day or \ntwo as a low- to mid-level subtropical ridge remains positioned to \nthe north. Thereafter, Odalys is forecast to slow considerably and \nturn sharply eastward by Tuesday, then east-northeastward through \nthe latter part of the week in response to a developing weakness in \nthe ridge as an upper-level trough deepens over the western United \nStates. Although the track guidance remains in decent agreement \nthrough the first half of the week, increasing cross-track spread \ndevelops thereafter. This appears to be due, at least in part, to \ndifferences in how the models handle the evolution of the \nupper-level trough over the western United States and the potential \ninfluence of another developing tropical cyclone tracking \nwest-northwestward offshore of southwestern Mexico. These factors \nlead to lower confidence in the track forecast during the latter \nportion of the forecast period. The NHC track forecast closely \nfollows the HCCA and GDMI aids through around day 4, then reflects \nmore of a blend of the two thereafter as the spread increases.\n\nEnvironmental conditions appear favorable for gradual strengthening \nduring the next couple of days, with warm sea surface temperatures \nand plenty of deep moisture expected along the forecast track. \nHowever, modest north-northeasterly vertical wind shear may temper \nthe rate of intensification during the next 24 h. Thereafter, the \nrate of strengthening could increase as the shear relaxes and Odalys \nremains in a favorable environment. The NHC forecast has the system \nbecoming a hurricane by Monday, with some additional strengthening \npossible through Tuesday. Thereafter, progressively drier mid-level \nair, along with increasing vertical wind shear anticipated later in \nthe forecast period, should induce a steady weakening trend. There \nis additional uncertainty in the intensity forecast due to the \npotential influence of another tropical cyclone evolving well to the \neast, which could affect its intensity depending on the eventual \ntracks and proximity of the two systems late in the week. The NHC \nintensity forecast lies near the middle to upper end of the guidance \nenvelope through much of the period.\n\n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  20/0900Z 11.4N 124.5W   35 KT  40 MPH\n 12H  20/1800Z 12.0N 125.6W   45 KT  50 MPH\n 24H  21/0600Z 13.3N 127.1W   55 KT  65 MPH\n 36H  21/1800Z 14.4N 128.3W   65 KT  75 MPH\n 48H  22/0600Z 15.0N 128.9W   70 KT  80 MPH\n 60H  22/1800Z 15.2N 128.7W   70 KT  80 MPH\n 72H  23/0600Z 15.3N 128.0W   65 KT  75 MPH\n 96H  24/0600Z 15.6N 126.5W   65 KT  75 MPH\n120H  25/0600Z 16.7N 124.8W   65 KT  75 MPH\n \n"}