802 WTNT43 KNHC 030238 TCDAT3 Hurricane Sam Discussion Number 42 NWS National Hurricane Center Miami FL AL182021 1100 PM AST Sat Oct 02 2021 Sam continues to gradually weaken. Conventional satellite imagery indicates that the eye has disappeared and that the cloud tops near the center are gradually warming. Various objective and subjective satellite intensity estimates are in the 90-102 kt range, while scatterometer and experimental synthetic aperture radar data suggest lower winds than that. The initial intensity is reduced to a possibly generous 100 kt. The initial motion is northeastward or 040/14 kt. A faster motion toward the northeast is expected during the next couple of days as Sam is steered by southwesterly flow between a deep-layer ridge to the east and a large mid- to upper-level low over Atlantic Canada. After Sam completes extratropical transition in about 48 h, a wobbly motion generally toward the northeast is expected as Sam interacts with one or more mid-latitude shortwave troughs. The new forecast track is similar to the previous track and lies close to the various consensus models. The hurricane is moving toward colder water, and it is approaching a frontal zone over the north Atlantic. The cyclone should undergo extratropical transition during the next couple of days, and due to a favorable interaction with a mid-latitude trough it should weaken only slowly as it becomes a large and powerful extratropical low by 48 h. After that time, the baroclinic forcing ends and the low should gradually spin down over the far north Atlantic. The new intensity forecast has only minor adjustments from the previous forecast. Key Messages: 1. Swells generated by Sam will impact the northern Leeward Islands, the Greater Antilles, the Bahamas, Bermuda, the eastern United States and Atlantic Canada for the next couple of days. These swells could cause life-threatening surf and rip current conditions. Please consult products from your local weather office. FORECAST POSITIONS AND MAX WINDS INIT 03/0300Z 36.4N 57.1W 100 KT 115 MPH 12H 03/1200Z 37.7N 55.3W 95 KT 110 MPH 24H 04/0000Z 39.7N 51.8W 90 KT 105 MPH 36H 04/1200Z 42.7N 47.0W 85 KT 100 MPH 48H 05/0000Z 47.3N 41.9W 80 KT 90 MPH...POST-TROP/EXTRATROP 60H 05/1200Z 50.8N 39.5W 75 KT 85 MPH...POST-TROP/EXTRATROP 72H 06/0000Z 51.7N 37.9W 65 KT 75 MPH...POST-TROP/EXTRATROP 96H 07/0000Z 54.0N 30.0W 50 KT 60 MPH...POST-TROP/EXTRATROP 120H 08/0000Z 60.5N 28.5W 40 KT 45 MPH...POST-TROP/EXTRATROP $$ Forecaster Beven