ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM Hurricane Lorenzo Discussion Number 38 NWS National Hurricane Center Miami FL AL132019 500 PM AST Tue Oct 01 2019 The eye of Lorenzo, while still evident in both visible and infrared satellite imagery, has become smaller and slightly less distinct this afternoon, but the overall structure of the hurricane has not changed much since the previous advisory. Objective Dvorak T-numbers crept up this morning when the eye cleared for a couple of hours and are somewhat higher than the latest subjective estimates from TAFB and SAB. A blend of these estimates remains around 85 kt, and this is the value used as the initial wind speed for this advisory. Lorenzo is heading toward colder waters and an area of increasing vertical wind shear. However, since the wind field of the hurricane is quite large, only gradually weakening is foreast during the next 12 to 24 hours. After that time, Lorenzo is forecast to merge with a front and become a strong extratropical low over the northeastern Atlantic. The global models indicate that the post-tropical low will weaken more quickly when it moves near Ireland and Great Britain in 2 to 3 days. Lorenzo continues to accelerate northeastward, with an initial motion estimate of 040/25 kt. The forward speed of the hurricane is predicted to increase further overnight and on Wednesday as it is steered northeastward ahead of a mid-latitude trough over the central Atlantic. By late Thursday, the post-tropical cyclone should slow down and turn eastward or east-southeastward within the low-level westerly flow. The track has continued to bend to the right beyond 48 hours, and the official forecast has once again been adjusted southward and eastward at that time period. The new NHC track forecast is in good agreement with the latest ECMWF model. Lorenzo is producing very large seas over the north Atlantic. Full information can be found in High Seas Forecasts from the following agencies: The NOAA Ocean Prediction Center under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php The UK Met Office under WMO header FQNT21 EGRR and online at http://www.metoffice.gov.uk/public/weather/marine-high-seas/ Meteo France under WMO header FQNT50 LFPW and online at http://www.meteofrance.com/previsions-meteo-marine/bulletin/ grandlarge/metarea2 Key Messages: 1. Lorenzo is expected to bring hurricane and tropical storm force winds to the Azores beginning tonight, and these conditions will continue into Wednesday. Hurricane and Tropical Storm Warnings are in effect for the Azores. 2. Swells generated by Lorenzo have spread across much of the North Atlantic, and are affecting the east coast of the United States, Atlantic Canada, the Bahamas, portions of the Greater and Lesser Antilles, and portions of the coast of Europe. These swells will produce life-threatening surf and rip currents. FORECAST POSITIONS AND MAX WINDS INIT 01/2100Z 37.0N 35.5W 85 KT 100 MPH 12H 02/0600Z 40.2N 31.3W 80 KT 90 MPH 24H 02/1800Z 45.6N 24.8W 70 KT 80 MPH 36H 03/0600Z 51.2N 18.4W 65 KT 75 MPH...POST-TROP/EXTRATROP 48H 03/1800Z 54.4N 13.5W 60 KT 70 MPH...POST-TROP/EXTRATROP 72H 04/1800Z 53.2N 3.0W 35 KT 40 MPH...POST-TROP/EXTRATROP 96H 05/1800Z...DISSIPATED $$ Forecaster Brown NNNN