Special Feature

NE Gulf of America (Invest AL91/T.D. Two): Recent satellite scatterometer wind data and nearby surface observations indicate that an area of low pressure located over the northeastern Gulf of America is becoming better defined. Therefore, AL91 has been upgraded to Tropical Depression Two. T.D. Two is centered near 28.0N 85.3W at 19/1500 UTC or 130 nm S of Panama City Florida, moving NNW at 2 kt. Estimated minimum central pressure is 1011 mb. Maximum sustained wind speed is 25 kt with gusts to 35 kt. Scattered moderate to strong convection prevails from 23N to 29N between 81W and 90W. Estimated seas to 5 ft are expected across the NE Gulf. On the forecast track, the depression will move near or along the northern Gulf coast during the next several days.

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 Two NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details.

Tropical Waves

A tropical wave in the eastern Atlantic is now along 35W, south of 19N, moving westward at 10 to 15 kt. No significant convection is noted near this wave due to dry Saharan air.

An Atlantic tropical wave is along 62W, south of 18N, moving westward at 15 to 20 kt. Scattered moderate convection is noted along the wave axis.

Monsoon Trough/ITCZ

The monsoon trough enters the Atlantic through the coast of Africa near 20N17W and continues southwestward to 09N41W. The ITCZ extends from 09N41W to 06N57W. Aside from the convection related to the tropical wave described above, no convection is noted at this time.

Gulf Of America

Please refer to the Special Features section for information on the recently upgraded T.D. Two.

Elsewhere, dry air dominates the remainder of the basin suppressing the development of showers and thunderstorms. A 1017 mb high pressure over the NW Gulf waters supports moderate to fresh NE winds and seas of 2-4 ft in the eastern Bay of Campeche, while light to gentle winds and slight seas prevail elsewhere.

For the forecast, T.D. Two will move to 28.2N 85.4W this evening, then strengthen to a tropical storm near 28.5N 85.7W Mon morning. Tropical Storm Two will be near 28.8N 86.0W Mon evening, 29.1N 86.4W Tue morning, 29.4N 87.3W Tue evening, and 29.7N 88.4W Wed morning. T.D. Two will change little in intensity as it moves near the Louisiana coast early Thu. Away from this system, weak high pressure will dominate, producing gentle to moderate winds and slight to moderate seas through the period.

Caribbean Sea

The subtropical ridge centered near 29N61W in the central Atlantic and extends westward to the coast of Florida. The pressure gradient to the south of the ridge is forcing strong to near-gale easterly trade winds across the central Caribbean, with the strongest winds occurring off Colombia. Rough seas are found in these waters. Moderate to fresh NE-E winds and moderate seas are present in the eastern Caribbean and Windward Passage. Elsewhere, light to gentle winds and slight to moderate seas are prevalent. Scattered showers and isolated thunderstorms that developed over Panama and Costa Rica have shifted inland, while scattered moderate convection associated with a tropical wave is moving into the southern Windward Islands. Generally dry weather conditions are noted elsewhere.

For the forecast, the pressure gradient between the western Atlantic high pressure ridge oriented along 28N, and the Colombian low will support NE winds pulsing to near gale-force across the waters N of Colombia tonight. Otherwise, strong winds and rough seas will prevail across the much of the central Caribbean into Mon, before contracting to south of 15N through Thu. East winds will pulse fresh to strong each evening through Tue in the Windward Passage.

Atlantic Ocean

A surface trough and an upper level low in the north-central tropical Atlantic combine to generate isolated showers north of 27N and between 37W and 44W. Meanwhile, a broad subtropical ridge centered over the central Atlantic forces fresh to strong easterly trade winds off northern Hispaniola as shown in a recent satellite scatterometer data. Elsewhere in the central and western Atlantic, moderate to fresh easterly winds and seas of 4-8 ft are occurring south of 24N and west of 45W, with highest seas to 8 ft E of the Windward Islands.

In the far eastern Atlantic, fresh to strong N to NE winds and seas of 4-8 ft are present north of the monsoon trough and east of 25W. Over the remainder of the basin, moderate or weaker winds and moderate seas prevail within the ridge axis.

For the forecast west of 55W, the western Atlantic subtropical ridge will weaken and drift northward early this week as a broad surface trough forms E of 50W. This trough will shift westward and reach 65W by Wed, then move W of 70W and weaken quickly Thu. Moderate to fresh trades will prevail S of 24N through Tue, with gentle winds to the N. Pulsing strong winds are expected during the evenings through Tue N of Hispaniola and in the Windward Passage. Expect increasing winds and seas N of 22N and E of 70W Tue through Wed night as the trough approaches.

Posted 53 minutes ago by NHC Forecaster Era