FLORIDA
STORMS
Hurricane Sam
LOCATED
645 MI SSE OF BERMUDA
WINDS
145 MPH
PRESSURE
938 MB
MOVING
NW AT 14 MPH
From the National Hurricane Center at 500 PM AST Thu Sep 30 2021
Intense hurricane Sam expected to bring large swells and dangerous high surf to a large portion of the western Atlantic shoreline.
TAP LINKS BELOW TO FOCUS
key messages
Alerts
hazards
summary
DISCUSSION

1. Swells generated by Sam will impact the Northern Leeward Islands and the Greater Antilles, including Puerto Rico, during the next few days. Swells are expected to reach Bermuda and the Bahamas by Friday, and then spread to the United States east coast by this weekend. These swells could cause life-threatening surf and rip current conditions. Please consult products from your local weather office.

2. Tropical storm conditions are expected on Bermuda beginning Friday night or early Saturday, and a Tropical Storm Warning has been issued for that island.

1. Swells generated by Sam will impact the Northern Leeward Islands and the Greater Antilles, including Puerto Rico, during the next few days. Swells are expected to reach Bermuda and the Bahamas by Friday, and then spread to the United States east coast by this weekend. These swells could cause life-threatening surf and rip current conditions. Please consult products from your local weather office.

2. Tropical storm conditions are expected on Bermuda beginning Friday night or early Saturday, and a Tropical Storm Warning has been issued for that island.

CHANGES WITH THIS ADVISORY: The Bermuda Weather Service has issued a Tropical Storm Warning for Bermuda. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for...
- Bermuda A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. For storm information specific to your area, please monitor products issued by your national meteorological service.

CHANGES WITH THIS ADVISORY: The Bermuda Weather Service has issued a Tropical Storm Warning for Bermuda. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for...
- Bermuda A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. For storm information specific to your area, please monitor products issued by your national meteorological service.

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.

WIND: Tropical storm conditions are expected on Bermuda beginning Friday night or early Saturday.

SURF: Swells generated by Sam will impact the northern Leeward Islands and the Greater Antilles, including Puerto Rico, during the next few days. Swells are expected to reach Bermuda and the Bahamas by Friday, and then spread to the United States east coast by this weekend. These swells could cause life threatening surf and rip current conditions. Please consult products from your local weather office.

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.

WIND: Tropical storm conditions are expected on Bermuda beginning Friday night or early Saturday.

SURF: Swells generated by Sam will impact the northern Leeward Islands and the Greater Antilles, including Puerto Rico, during the next few days. Swells are expected to reach Bermuda and the Bahamas by Friday, and then spread to the United States east coast by this weekend. These swells could cause life threatening surf and rip current conditions. Please consult products from your local weather office.

At 500 PM AST (2100 UTC), the eye of Hurricane Sam was located by an Air Force Hurricane Hunter aircraft near latitude 23.6 North, longitude 60.9 West. Sam is moving toward the northwest near 14 mph (22 km/h), and a turn toward the north northwest with an additional increase in forward speed is expected tonight. A turn toward the north is anticipated on Friday, and a northeastward motion is forecast to begin on Saturday. On the forecast track, the core of Sam will pass to the east of Bermuda early Saturday. Maximum sustained winds are near 145 mph (230 km/h) with higher gusts. Sam is a category 4 hurricane on the Saffir Simpson Hurricane Wind Scale. Some fluctuations in intensity are expected during the next couple of days, but Sam is forecast to remain a major hurricane into Saturday, with more significant weakening anticipated later in the weekend.

Hurricane force winds extend outward up to 60 miles (95 km) from the center and tropical storm force winds extend outward up to 150 miles (240 km). The minimum central pressure reported by the Hurricane Hunters is 938 mb (27.70 inches).

At 500 PM AST (2100 UTC), the eye of Hurricane Sam was located by an Air Force Hurricane Hunter aircraft near latitude 23.6 North, longitude 60.9 West. Sam is moving toward the northwest near 14 mph (22 km/h), and a turn toward the north northwest with an additional increase in forward speed is expected tonight. A turn toward the north is anticipated on Friday, and a northeastward motion is forecast to begin on Saturday. On the forecast track, the core of Sam will pass to the east of Bermuda early Saturday. Maximum sustained winds are near 145 mph (230 km/h) with higher gusts. Sam is a category 4 hurricane on the Saffir Simpson Hurricane Wind Scale. Some fluctuations in intensity are expected during the next couple of days, but Sam is forecast to remain a major hurricane into Saturday, with more significant weakening anticipated later in the weekend.

Hurricane force winds extend outward up to 60 miles (95 km) from the center and tropical storm force winds extend outward up to 150 miles (240 km). The minimum central pressure reported by the Hurricane Hunters is 938 mb (27.70 inches).

Sam remains a formidable hurricane, with a well-organized cloud pattern on satellite imagery. The 25 n mi wide eye is surrounded by a fairly symmetric pattern of deep convective cloud tops, and the upper-level outflow pattern is very well defined. An Air Force Reserve Unit Hurricane Hunter aircraft investigated the system and found peak 700-mb flight level winds of 133 kt, and a highest unflagged SFMR-observed surface wind of 125 kt. Based on these observations, the advisory intensity is kept at 125 kt. Measurements from the aircraft also showed that the central pressure remains quite low, near 938 mb.

Sam will continue to traverse waters of high oceanic heat content for another 12-18 hours, and the shear should remain fairly low for the next few days. Therefore, some intensification could still occur overnight. In any event, the system is expected to maintain major hurricane status for the next 36-48 hours. Over the weekend, a gradual weakening trend should commence due to cooler SSTs. However, Sam will likely remain a powerful cyclone with hurricane- force winds until the end of the forecast period. By 120 hours, simulated satellite imagery from the ECMWF and GFS models forecast the system's cloud pattern to resemble that of an extratropical low, and this is reflected in the official forecast, which shows extratropical status at that time. The official intensity forecast remains close to the HCCA corrected consensus model solution.

Center fixes continue to show a gradual increase in forward speed, and the hurricane is moving northwestward, or about 320/12 kt. During the next 24-36 hours, Sam should turn toward the north as it moves around the western periphery of a large subtropical high over the eastern and central Atlantic. Then, the cyclone is expected to move generally northeastward in the flow between the anticyclone and a trough near Atlantic Canada. There is fairly close agreement in the track models through 60 hours or so. However, there are some significant differences in the model-predicted track of Sam at higher latitudes, probably due to variations in how the system interacts with the trough in the various guidance. The NHC track forecast follows the latest model consensus, TVCN.

Although the core of Sam is predicted to pass east of Bermuda early Saturday, the tropical-storm-force wind field is forecast to expand and could pass very close to the island beginning late Friday night or early Saturday. Therefore, a Tropical Storm Warning has been issued for Bermuda.

Sam remains a formidable hurricane, with a well-organized cloud pattern on satellite imagery. The 25 n mi wide eye is surrounded by a fairly symmetric pattern of deep convective cloud tops, and the upper-level outflow pattern is very well defined. An Air Force Reserve Unit Hurricane Hunter aircraft investigated the system and found peak 700-mb flight level winds of 133 kt, and a highest unflagged SFMR-observed surface wind of 125 kt. Based on these observations, the advisory intensity is kept at 125 kt. Measurements from the aircraft also showed that the central pressure remains quite low, near 938 mb.

Sam will continue to traverse waters of high oceanic heat content for another 12-18 hours, and the shear should remain fairly low for the next few days. Therefore, some intensification could still occur overnight. In any event, the system is expected to maintain major hurricane status for the next 36-48 hours. Over the weekend, a gradual weakening trend should commence due to cooler SSTs. However, Sam will likely remain a powerful cyclone with hurricane- force winds until the end of the forecast period. By 120 hours, simulated satellite imagery from the ECMWF and GFS models forecast the system's cloud pattern to resemble that of an extratropical low, and this is reflected in the official forecast, which shows extratropical status at that time. The official intensity forecast remains close to the HCCA corrected consensus model solution.

Center fixes continue to show a gradual increase in forward speed, and the hurricane is moving northwestward, or about 320/12 kt. During the next 24-36 hours, Sam should turn toward the north as it moves around the western periphery of a large subtropical high over the eastern and central Atlantic. Then, the cyclone is expected to move generally northeastward in the flow between the anticyclone and a trough near Atlantic Canada. There is fairly close agreement in the track models through 60 hours or so. However, there are some significant differences in the model-predicted track of Sam at higher latitudes, probably due to variations in how the system interacts with the trough in the various guidance. The NHC track forecast follows the latest model consensus, TVCN.

Although the core of Sam is predicted to pass east of Bermuda early Saturday, the tropical-storm-force wind field is forecast to expand and could pass very close to the island beginning late Friday night or early Saturday. Therefore, a Tropical Storm Warning has been issued for Bermuda.

Partners of the Florida Public Radio Emergency Network include:  WDNA (Miami), WFIT (Melbourne), WMFE (Orlando), WFSU (Tallahassee), WGCU (Fort Myers), WJCT (Jacksonville), WKGC (Panama City), WLRN (Miami), WMNF (Tampa-Sarasota), WQCS (Fort Pierce), WUFT (Gainesville-Ocala), WUSF (Tampa), WUWF (Pensacola) and Florida Public Media.

1885 Stadium Road

PO Box 118400

Gainesville, FL 32611

(352) 392-5551

Loading...
linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram