ZCZC MIATCDAT4 ALL TTAA00 KNHC DDHHMM Hurricane Margot Discussion Number 21 NWS National Hurricane Center Miami FL AL142023 300 PM GMT Tue Sep 12 2023 After a brief hiatus, Margot has redevloped a fairly clear eye. Cloud-top temperatures around that eye are cold enough to support satellite intensity estimates similar to the previous advisory and the intensity is held at 75 kt. The big change with this advisory is that ASCAT data valid between 12 and 13 UTC revealed Margot has grown substantially, with 34 kt and 50 kt winds extending much farther from the center of the hurricane than previously estimated. Microwave data also suggest the presence of a double eyewall. There is high confidence in the track forecast for the next 3 days. Margot should turn north-northwestward tomorrow while it slows down. After that, there is considerable uncertainty in the strength of a ridge that is forecast to build to the north of Margot. The GFS and ECMWF are on opposite ends of the spectrum, with the GFS showing Margot moving faster to the north due to a weaker blocking high. Confidence in the track forecast decreases at day 4 and 5 given the high spread. The NHC forecast is near the multi-model consensus, but relatively large changes could be required to later advisories if one model solution or another becomes more likely. The aforementioned ASCAT passes also showed that despite the relatively small eye of Margot, the wind field is fairly spread out, which may limit the potential for substantial further intensification. Most of the hurricane models seem to have a good handle on this, showing Margot more or less maintaining its intensity for the next several days. Weakening should begin after 3 days as Margot moves over cooler waters, wind shear increases, and possibly its transition to an extratropical cyclone begins. FORECAST POSITIONS AND MAX WINDS INIT 12/1500Z 30.2N 39.4W 75 KT 85 MPH 12H 13/0000Z 31.8N 40.0W 80 KT 90 MPH 24H 13/1200Z 33.3N 41.0W 80 KT 90 MPH 36H 14/0000Z 34.3N 41.6W 75 KT 85 MPH 48H 14/1200Z 35.3N 41.6W 75 KT 85 MPH 60H 15/0000Z 36.3N 41.4W 70 KT 80 MPH 72H 15/1200Z 37.0N 41.5W 70 KT 80 MPH 96H 16/1200Z 38.5N 43.0W 55 KT 65 MPH 120H 17/1200Z 40.5N 43.0W 45 KT 50 MPH $$ Forecaster D. Zelinsky NNNN