571 AXNT20 KNHC 131157 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 757 AM EDT Fri Jul 13 2018 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 1115 UTC. ...SPECIAL FEATURES... ...Gale Warning off the coast of Colombia in the Caribbean Sea... The most recent scatterometer data provided observations of minimal gale force NE-E winds across the south-central Caribbean, particularly from 11N to 13N between 74W and 76W. Sea heights range from 10 feet to 14 feet. These conditions are forecast to occur again tonight. Please, see the High Seas Forecast, under the AWIPS/WMO headers HSFAT2/FZNT02 KNHC, for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 38W from 06N-19N. Scattered moderate convection is noted from 07N to 12N between 33W and 40W, near the monsoon trough/ ITCZ. An Atlantic Ocean tropical wave is along 54W from 06N-20N. Convection is limited near the wave's axis due to the presence of African dust. A Caribbean Sea tropical wave is along 68W from 07N-17N. This wave continue to enhance some shower activity over Venezuela. A tropical wave has its axis over the Yucatan Peninsula and Guatemala, and extends southward into the EPAC region. Currently, scattered showers are near the wave's axis. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Senegal to near 11N32. The ITCZ extends from 07N40W to 07N50W to 10N61W. Scattered moderate convection is from 05N-08N between 43W-50W. Similar convection is from 8=08N-10.5N between 56W-62W. ...DISCUSSION... GULF OF MEXICO... Weak high pressure will continue across the area through Mon. A surface trough will move westward off the Yucatan Peninsula each evening through tUE. It will tend to enhance nocturnal winds and seas over the SW Gulf. A tropical wave will move westward across the Bay of Campeche in the SW Gulf today. CARIBBEAN SEA... A gale warning is in effect in the central Caribbean near the coast of Colombia. Winds will diminish below gale force this morning, and are expected to reach minimal gale force again tonight, exceeding 30 kt each night afterwards through early Mon. A series of westward moving tropical waves lined up from the eastern Caribbean across the Atlantic to near 35W will pass quickly across the region through Tue. High pressure will build behind each passing tropical wave to freshen trade winds in the region, particularly across the central Caribbean. ATLANTIC OCEAN... A weak area of low pressure, associated with the remnants of Beryl, has formed about 300 miles west of Bermuda, but showers and thunderstorms associated with this system remain disorganized due to strong upper-level winds. These winds are expected to become even less conducive for tropical or subtropical development over the next day or two while the low moves north-northeastward at about 10 mph, and development will be limited once the low reaches colder waters by Saturday night or Sunday. The latest Tropical Weather Outlook gives this system a low chance of tropical cyclone formation during the next 48 hours. A surface trough extends from the aforementioned weak low to central Florida. This trough will linger over the area through Sun. High pressure will build westward from the central Atlantic through Mon, supporting fresh to strong trade winds mainly S of 23N W of 65W. Winds are expected to pulse to locally strong just north of Hispaniola at night this weekend. The remainder of the Atlantic forecast area is under the influence of the Bermuda-Azores High with a center of 1034 mb located WNW of the Azores near 40N38W. The ridge extends SW into the NE Caribbean. The Saharan Air Layer (SAL) from CIMSS depicts a surge of African dust over the eastern Atlantic, and behind the tropical wave along 54W. For additional information please visit http://www.hurricanes.gov/marine $$ GR