{"id": "1214669757852024839", "title": "Tropical Cyclone Discussion", "adv_date": "2026-09-30T09:00:00Z", "msg": "432\nWTPZ43 KNHC 300849\nTCDEP3\n \nHurricane Rachel Discussion Number  13\nNWS National Hurricane Center Miami FL       EP182026\n200 AM MST Wed Sep 30 2026\n\nRachel is becoming better organized as the north-northeasterly \nvertical wind shear over the system appears to be relaxing.  After \nstrengthening into a hurricane around 0600 UTC, the system is \ndeveloping better-defined convective banding features, \nespecially over the western quadrant of the circulation.  Deep \nconvection remains very intense, with numerous cloud tops as cold \nas -80 deg C.  A NOAA Hurricane Hunter aircraft flying a research \nmission into Rachel measured 84-kt winds at the 700 mb flight \nlevel.  Based on this observation and the increased organization on \nsatellite images, the advisory intensity is set to 75 kt.  This is \nsomewhat higher than the subjective Dvorak estimate and objective \nestimates from UW-CIMSS.\n\nThe forward speed has slowed somewhat and the current motion \nestimate is 315/9 kt.  Rachel continues to move along the \nsouthwestern side of a mid-tropospheric ridge over northern and \ncentral Mexico.  The ridge is weakening due to the passage of a \nmid- to upper-level trough/low over the southern United States, and \nthis is gradually slowing the steering current.  As the low lifts \nnorthward during the next couple of days, this should allow another \nridge to build to the north of the tropical cyclone.  As a result, \nRachel is forecast to turn toward the west-northwest and pass well \nsouth of the Baja California Peninsula before continuing westward \naway from land. The official track forecast is similar to, but \nslightly slower than, the previous NHC prediction.  This is a blend \nof the latest HFIP Corrected Consensus Approach (HCCA) and Google \nDeepMind guidance.\n\nGiven the decrease in vertical shear, and expected passage over \nvery warm waters, significant strengthening seems likely during the \nnext 24-36 hours.  The SHIPS Rapid Intensification (RI) guidance \nindicates a substantially higher than normal probability of RI.  \nThe official intensity forecast anticipates that Rachel will \nquickly strengthen into a major hurricane by tomorrow if not \nsooner.  This is also similar to the latest HCCA prediction.\nBeyond 48 hours, drier low- to mid-level air could cause some \nweakening.  The NHC intensity forecasts is on the high side of the \nmodel guidance envelope.\n\nThe outer wind radii were adjusted based on data from recent \nASCAT-B/C overpasses.\n \n \nKey Messages:\n \n1. Although the core of Rachel is forecast to remain offshore of\nMexico, tropical-storm-force winds are expected along a portion of\nthe coast of southwestern Mexico in the warning area this morning.\n \n2. Outer bands from Rachel will bring locally heavy rainfall to \nportions of coastal southwest Mexico through Thursday. This rainfall \nmay produce life-threatening flooding and mudslides, especially in \nareas of steep terrain.\n \n3. Large waves could produce life-threatening surf and rip current\nconditions along the southwestern and west-central coast of Mexico\nand the southern Baja California Peninsula during the next several\ndays.\n \n \nFORECAST POSITIONS AND MAX WINDS\n \nINIT  30/0900Z 17.6N 107.2W   75 KT  85 MPH\n 12H  30/1800Z 18.4N 108.1W   90 KT 105 MPH\n 24H  01/0600Z 19.2N 109.1W  100 KT 115 MPH\n 36H  01/1800Z 19.5N 109.7W  105 KT 120 MPH\n 48H  02/0600Z 19.7N 110.4W  105 KT 120 MPH\n 60H  02/1800Z 19.9N 111.1W  100 KT 115 MPH\n 72H  03/0600Z 20.1N 112.2W   90 KT 105 MPH\n 96H  04/0600Z 20.4N 114.3W   90 KT 105 MPH\n120H  05/0600Z 20.8N 116.3W   85 KT 100 MPH\n \n"}