000 WTPZ44 KNHC 211456 TCDEP4 Tropical Storm Roslyn Discussion Number 7 NWS National Hurricane Center Miami FL EP192022 1000 AM CDT Fri Oct 21 2022 Visible satellite imagery suggests that Roslyn is getting better organized, with the formation of a central dense overcast with overshooting tops near the center. A recent GMI overpass indicates these tops are related to a partial eyewall that has formed under the overcast. The various subjective and objective satellite intensity estimates remain near 55 kt, and based on these data the initial intensity is unchanged from the previous advisory. One note is that there seem to be a tongue of dry air wrapping cyclonically around the CDO from the northwest to southeast. It should be noted that the Air Force Reserve Hurricane Hunter mission scheduled for this afternoon has been canceled due to mechanical issues. The recent satellite data suggest that the center is a little south of the previous track, and the initial motion is a somewhat uncertain 300/6 kt. Despite this shift, there is little change in the track forecast philosophy from the previous advisory, as Roslyn is still expected to recurve around the western edge of a mid-level ridge that will migrate eastward across Mexico during the next couple of days. This will lead to the center passing near or a little west of Cabo Corrientes in about 36 h, followed by landfall in mainland Mexico. There is little change to either the forecast guidance or the official forecast track since the last advisory, and the new track lies near or just east of the various consensus models. Since Roslyn is developing a better defined inner core, its current environment of light shear and warm sea surface temperatures could allow for rapid intensification. One obstacle to that, though, is the dry air currently near the core. The GFS, HRWF, and HMON models forecast this dry air to get mixed out during the next 12-24 h, and based on this premise, the new intensity forecast will follow the previous forecast in showing rapid strengthening to a peak intensity of 95 kt before landfall. After landfall, Roslyn is expected to rapidly weaken over the mountains of Mexico, and although the official forecast shows a remnant low over northern Mexico in 72 hours for continuity, Roslyn will likely dissipate before then. The new forecast requires a northward extension of the hurricane warning along the coast of Mexico. Additional watches and warnings will likely be required on the next advisory. Key Messages: 1. Roslyn is forecast to be a hurricane when it passes near and makes landfall along the west-central coast of Mexico late Saturday and Sunday, accompanied by strong winds and a potentially dangerous storm surge. A Hurricane Warning is now in effect for a portion of the west-central coast of Mexico and will likely be extended northward later today. 2. Heavy rainfall could lead to flash flooding and possible landslides in areas of rugged terrain over coastal southwestern and west-central Mexico. FORECAST POSITIONS AND MAX WINDS INIT 21/1500Z 16.4N 104.4W 55 KT 65 MPH 12H 22/0000Z 17.0N 105.1W 70 KT 80 MPH 24H 22/1200Z 18.1N 106.0W 85 KT 100 MPH 36H 23/0000Z 19.6N 106.3W 95 KT 110 MPH 48H 23/1200Z 21.7N 105.8W 95 KT 110 MPH 60H 24/0000Z 24.4N 104.4W 45 KT 50 MPH...INLAND 72H 24/1200Z 27.1N 102.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 25/1200Z...DISSIPATED $$ Forecaster Beven