ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM Post-Tropical Cyclone Lorenzo Discussion Number 41 NWS National Hurricane Center Miami FL AL132019 1100 AM AST Wed Oct 02 2019 Lorenzo has completed its transition into a powerful extratropical cyclone and this will be the last NHC advisory on this system. The center has become exposed on the southwestern edge of the cloud shield, and recent ASCAT data indicate that the system has acquired frontal features. The initial intensity is set at 70 kt, which is a little above the scatterometer data since there is typically a low bias in that instrument at these wind speeds. The global models suggest that the post-tropical cyclone will only gradually weaken during the next 24 to 36 hours as it approaches Ireland. A faster rate of weakening is expected Thursday night and Friday when the cyclone moves southeastward over Ireland and the United Kingdom. The low should dissipate over southeastern England by late Friday. The cyclone continues to move rapidly northeastward or 040/37 kt, and this general motion should continue into Thursday. After that time, the cyclone is expected to turn eastward and then southeastward within an area of weaker westerly flow. The global model guidance is in good agreement, and the NHC track forecast is in closest to the ECMWF model. Future hazard information on Lorenzo for Ireland and the United Kingdom can be found in products issued by Met Eireann and the United Kingdom Met Office. Local forecasts and warnings for Ireland can be found on the website of Met Eireann, the Irish Meteorological Service, at http://www.met.ie/. Local forecasts and warnings for the United Kingdom can be found on the website of the UK Met Office at http://www.metoffice.gov.uk/. Lorenzo's expansive circulation 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 https://www.metoffice.gov.uk/weather/specialist-forecasts/coast-and- sea/high-seas-forecast Meteo France under WMO header FQNT50 LFPW and online at http://www.meteofrance.com/previsions-meteo-marine/bulletin/ grandlarge/metarea2 FORECAST POSITIONS AND MAX WINDS INIT 02/1500Z 44.4N 25.8W 70 KT 80 MPH...POST-TROPICAL 12H 03/0000Z 48.6N 20.8W 70 KT 80 MPH...POST-TROP/EXTRATROP 24H 03/1200Z 52.8N 14.3W 65 KT 75 MPH...POST-TROP/EXTRATROP 36H 04/0000Z 54.0N 9.5W 60 KT 70 MPH...POST-TROP/EXTRATROP 48H 04/1200Z 52.5N 3.5W 40 KT 45 MPH...POST-TROP/EXTRATROP 72H 05/1200Z...DISSIPATED $$ Forecaster Brown NNNN