CURRENT TROPICAL CYCLONES:
Tropical Cyclone 18L (Sam)…is located about 490 miles east of the northern Leeward Islands
Tropical Cyclone 18L (Sam)
SAM SLOWLY STRENGTHENING WITH 140-MPH WINDS
According to the NHC Advisory 26…Sam is moving toward the northwest near 9 mph (15 km/h), and this general motion with an increase in forward speed is expected during the next couple of days. A turn toward the north is forecast by Friday. On the forecast track, Sam will pass well to the east and northeast of the northern Leeward Islands through Wednesday. Maximum sustained winds are near 140 mph (220 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 through late this week. Hurricane-force winds extend outward up to 40 miles (65 km) from the center and
HAZARDS AFFECTING LAND
SURF: Swells generated by Sam will impact the Lesser Antilles for the next several days. Swells are expected to reach Bermuda and the Bahamas in a couple of days, and then spread to the United States east coast late this week. These swells could cause life-threatening surf and rip current conditions.
Recent satellite-derived surface wind data indicate that the low pressure system located over the far eastern tropical Atlantic several hundred miles south of the Cabo Verde Islands is gradually becoming better defined. The associated showers and thunderstorms are showing signs of organization, and a tropical depression is expected to form during the next day or so while the disturbance moves west-northwestward at 10 to 15 mph over the eastern tropical Atlantic.
* Formation chance through 48 hours…high…90 percent
* Formation chance through 5 days…high…90 percent
>>> Showers and thunderstorms remain disorganized in association with a a broad area of low pressure located several hundred miles southwest of the Cabo Verde Islands. Environmental conditions are conducive for gradual development, and a tropical depression could still form during the next couple of days if the disturbance does not get absorbed into the stronger low pressure system located to its east. The broad low is expected to move slowly west-northwestward to westward over the central tropical Atlantic during the next few days.
* Formation chance through 48 hours…medium…60 percent
* Formation chance through 5 days…medium…60 percent
A well-defined low pressure area associated with the remnants of Peter is located several hundred miles east-northeast of Bermuda. The associated shower and thunderstorm activity remains limited, and the chances of this system becoming a short-lived tropical depression or storm appear to be decreasing. This system is expected to move northeastward at about 10 mph into a region of very strong upper-level winds on Wednesday.
* Formation chance through 48 hours…low…30 percent
* Formation chance through 5 days…low…30 percent