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.

There are no coastal watches or warnings in effect.

Key messages for Sam can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT3 and WMO header WTNT43 KNHC, and on the web at hurricanes.gov/graphics_at3.shtml?key_messages.

SURF: Swells generated by Sam will impact the northern Leeward Islands, the Greater Antilles, the Bahamas, 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.

At 500 AM AST (0900 UTC), the center of Hurricane Sam was located near latitude 37.3 North, longitude 55.9 West. Sam is moving toward the northeast near 17 mph (28 km/h). This general motion with an increase in forward speed is expected during the next few days. On the forecast track, Sam will move over the far North Atlantic well to southeast and east of Newfoundland. Maximum sustained winds decreased to near 105 mph (165 km/h) with higher gusts. Further weakening is forecast during the next few days, and Sam is expected transition into a powerful post tropical cyclone on Monday. Hurricane force winds extend outward up to 45 miles (75 km) from the center and tropical storm force winds extend outward up to 240 miles (390 km). The estimated minimum central pressure is 960 mb (28.35 inches).

Sam has continued to weaken since the previous advisory, with cloud tops in the central dense overcast (CDO) having warmed to -60 to -65 deg C near the center. However, the upper-level outflow pattern remains impressive The initial intensity has been lowered to 90 kt based on an average of the current data-T number of 4.5/77 kt and current intensity (CI) estimate of 5.5/102 kt from TAFB, and a 0530 UTC UW-CIMSS SATCON intensity estimate of 89 kt. Further weakening during the is expected as Sam moves over progressively cooler water and southwesterly vertical wind shear of 20-25 kt continues. By 18-24 hours, Sam will be moving north of the north wall of the Gulfstream, resulting in extratropical transition due to the cyclone moving over sub-20-deg-C sea-surface temperatures. However, favorable interaction with a strong mid-tropospheric trough will result in Sam becoming a large and powerful extratropical low with hurricane-force winds in 36-48 hours. Thereafter, Sam's wind field is expected gradually spin down over the far north Atlantic when baroclinic forcing will cease. he new intensity forecast is similar to but slightly lower than the previous intensity forecast.

The initial motion is northeastward, or 045/15 kt. The latest NHC model guidance is tightly clustered around the previous track forecast, and thus, no significant changes were made to the previous advisory track. A faster northeastward motion is expected during the next couple of days, followed by a slow down in the forward motion as Sam becomes entangled with an upper-level cutoff low. The new track forecast is essentially down the middle of the tightly packed simple and corrected-consensus models.

Recent ASCAT-A surface wind data indicate that no significant adjustments to the 34- and 50-kt wind radii were needed, but that the size of the 64-kt wind radii had to be decreased somewhat.