Based on 1200 UTC surface analysis and satellite imagery through 1600 UTC.

Special Features

Tropical Storm Gabrielle is centered near 25.2N 58.7W at 20/1800 UTC or 520 nm NNE of the Northern Leeward Islands, moving NW at 11 kt. Estimated minimum central pressure is 996 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Peak seas are 22 ft, with seas greater than 8 ft analyzed north of 23N between 55W and 65W. Numerous moderate scattered strong convection is from 23N to 27N between 55W and 60W. A turn toward the north-northwest is forecast on Sunday, followed by a turn toward the north and northeast Monday and Monday night. On the forecast track, the center of Gabrielle is expected to pass east of Bermuda Sunday night and Monday. Continued gradual strengthening is forecast, and Gabrielle is expected to become a hurricane by Sunday. Air Force Reserve and NOAA Hurricane Hunter aircraft are currently investigating Gabrielle. Swells generated by Gabrielle are beginning to reach Bermuda and will build through the weekend. Swells generated by Gabrielle should reach the east coast of the United States from North Carolina northward, along with Atlantic Canada, later this weekend into early next week. These swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office.

Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest Gabrielle NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details.

Tropical Waves

A far eastern Atlantic tropical wave has its axis near 29W, south of 20N, moving westward at 15-20 kt. Scattered moderate convection is noted from 08N to 15N between 25W and 35W.

A central Atlantic Ocean tropical wave has its axis near 43W, south of 21N, moving westward at 15-20 kt. Scattered showers are in the vicinity of the wave axis.

Upper Air Sounding Data from Kingston, Jamaica, indicates a tropical wave is along 78W, from 20N southward across Jamaica to Panama. The tropical wave appears to have briefly stalled in the W Caribbean; no significant convection is noted at this time.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic near Dakar, Senegal, and continues southwestward to 07N45W. The ITCZ extends from 07N45W to South America, where the boundary runs along the coasts of French Guiana and Suriname. Convection along the Monsoon Trough is described in the tropical waves section, and only a few showers are evident along the ITCZ.

Gulf Of America

Diffuse 1019 high pressure centered along the north-central Gulf coast provides for light to gentle E winds and 1-3 ft seas across the basin. Scattered showers and tstorms are evident on satellite in the southern Bay of Campeche and in the south-central Gulf.

For the forecast, surface ridging will continue to control the general weather pattern through the weekend before shifting NE and weakening into next week. With Tropical Cyclone Gabrielle over the Atlantic lifting northward through Mon night, Atlantic ridging will build westward along the northern Gulf early next week. Mainly gentle to moderate winds and slight seas will prevail across the basin.

Caribbean Sea

Refer to the section above for details on the tropical wave moving across the basin.

An upper-level trough continues to extend across the Atlantic from south of Bermuda to the Mona Passage, then across the central Caribbean to eastern Panama. Scattered moderate convection is west of 86W in the NW Caribbean and Gulf of Honduras, including coastal sections of Belize and Quintana Roo, Mexico. Shower activity is limited to the lee of Cuba. Across the basin, light to gentle trades and 1-3 ft seas prevail. Winds and seas may be locally higher in the Atlantic Passages, as minor swells from Tropical Storm Gabrielle arrive.

For the forecast, scattered showers and thunderstorms will persist in the Gulf of Honduras today. Similar weather is in the NE Caribbean including near the Atlantic Passages due to an induced trough. Gentle to moderate trades along with moderate seas are expected through Sun, increasing slightly thereafter basinwide as the pressure gradient tightens in the wake of Tropical Cyclone Gabrielle moving through the central Atlantic. Fresh to strong winds may pulse in the S-central portion of the basin Mon night.

Atlantic Ocean

Refer to the sections above for details on Tropical Storm Gabrielle, and on the tropical waves across the eastern Atlantic.

A surface trough persists across the central Bahamas, along roughly 74/75W. Moderate to locally fresh NE winds are west of the trough to the coast of Florida. Scattered showers and thunderstorms are active within 60 nm east of the trough, across the central Bahamas. Weak 1020 mb low pressure is centered near 28N34W. 1024 mb high pressure is centered near 31N49W. Outside of the influence of TROPICAL STORM GABRIELLE, this morning's scatterometer passes indicate gentle to moderate trades across the basin. Seas are analyzed within 4-7 ft in open waters.

For the forecast west of 55W, Tropical Storm Gabrielle will move to 26.2N 60.0W this evening, strengthen to a hurricane near 27.8N 61.2W Sun morning, 29.4N 62.0W Sun evening, moving just N of the area to 31.1N 61.9W Mon morning, 32.8N 60.4W Mon evening, and 34.5N 57.7W Tue morning. Gabrielle will change little in intensity as it moves well NNE of the area to 37.0N 48.4W early Wed. A surface trough will persist off the SE U.S. Coast to the northern Bahamas through at least the weekend enhancing convection in the vicinity. Otherwise, in the wake of Gabrielle, central Atlantic high pressure will build westward generally providing for light to gentle winds over the central and western portions of the area, and for gentle to moderate winds over the eastern portion into midweek. Seas associated with Gabrielle will gradually subside by midweek.

Posted 1 hour, 35 minutes ago by NHC Forecaster Mahoney