000 AXNT20 KNHC 201016 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 616 AM EDT Thu Aug 20 2020 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 1000 UTC. ...SPECIAL FEATURES... Tropical Depression Thirteen is centered near 15.2N 49.8W at 20/0900 UTC or 790 nm E of the Northern Leeward Islands moving WNW at 18 kt. Estimated minimum central pressure is 1008 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Scattered moderate to isolated strong convection stretches from 10N to 20N between 46W and 53W. Seas are up to 10 ft near the center. On the forecast track, the depression will move near the Leeward Islands late Friday into early Saturday, near or north of the Virgin Islands and Puerto Rico Saturday or Saturday night, then near Hispaniola and the SE Bahamas early Sun. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT3.shtml and Forecast/Advisory at https://www.nhc.noaa.gov/text/MIATCMAT4.shtml for more details. Low pressure of 1008 mb near 15N78W is moving west at 15 to 20 kt and is producing showers and thunderstorms over the central Caribbean Sea. This system is gradually becoming better organized, and a tropical depression is likely for form in a couple of days when the system reaches the NW Caribbean Seas. Interests in Honduras and the Yucatan Peninsula should closely monitor its progress. Regardless of development, this disturbance will likely produce heavy rains across a large portion of Central America and southeastern Mexico late this week and this weekend. Formation chance through 48 hours is high. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov, for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is emerging off the west coast of Africa around 18W from 18N southward, moving west at 15 kt. Scattered moderate convection is occurring within 180 nm either side of this tropical wave. An Atlantic Ocean tropical wave has an axis along 43W from 19N southward and is moving west at 15 knots. Scattered moderate convection has developed in association with this wave from 09N to 12N between 35W and 43W. An Atlantic Ocean tropical wave has an axis along 60W from 20N southward and is moving westward 15-20 kt knots. Convection previously associated with this wave has diminished. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Mauritania near 19N16W to 12N34W. The ITCZ begins near 12N49W to the coast of Guyana near 08N60W. Convection along these two features is associated with systems described above in the Special Features and Tropical Waves sections. GULF OF MEXICO... A stationary front resides along the Louisiana coast, with a weak surface trough extending in the northern Gulf from 30N89W to 24N92W. Broad ascent over the northeast Gulf is leading to scattered moderate to isolated strong convection N of 23N and E of 91W. Elsewhere, light to gentle winds and seas of less than 2 ft prevail. For the forecast, Tropical Depression Thirteen near 15.2N 49.8W 1008 mb at 5 AM EDT moving WNW at 18 kt. Maximum sustained winds 30 kt gusts 40 kt. Thirteen will move to 16.4N 52.7W this afternoon and strengthen to a tropical storm near 17.5N 56.4W Fri morning. The tropical storm will then reach near 18.4N 60.2W Fri afternoon, 19.1N 63.9W Sat morning, 19.8N 67.1W Sat afternoon, and 20.8N 71.0W Sun morning. Thirteen is forecast to remain a tropical storm as it passes near eastern Cuba and the southeastern Bahamas early Mon. This system could impact portions of the eastern Gulf of Mexico early next week. Meanwhile, low pressure over the central Caribbean Sea this morning has a high chance of tropical formation in the northwest Caribbean within a couple of days. Interests in the Yucatan Peninsula should closely monitor the progress of this low, which could impact the central and western Gulf of Mexico for the start of next week. CARIBBEAN SEA... See above discussion in Special Features for the low pressure over the Caribbean. For the portions of the eastern and western Caribbean sea not being impacted by the low pressure, gentle to moderate trades are occurring. Scattered convection is confined to areas along the Pacific monsoonal trough, within about 180 nm of the Panama coast. Seas range 3-6 ft with upwards of 9 ft near the low in the central Caribbean. Tropical Depression Thirteen near 15.2N 49.8W 1008 mb at 5 AM EDT moving WNW at 18 kt. Maximum sustained winds 30 kt gusts 40 kt. Thirteen will move to 16.4N 52.7W this afternoon and strengthen to a tropical storm near 17.5N 56.4W Fri morning. The tropical storm will then reach near 18.4N 60.2W Fri afternoon, 19.1N 63.9W Sat morning, 19.8N 67.1W Sat afternoon, and 20.8N 71.0W Sun morning. Thirteen is forecast to remain a tropical storm as it passes near eastern Cuba and the southeastern Bahamas early Mon. Meanwhile, low pressure over the central Caribbean Sea this morning has a high chance of tropical formation in the northwest Caribbean within a couple of days. Regardless of development, heavy rainfall is expected across a large part of Central America and SE Mexico through the weekend. ATLANTIC OCEAN... See above discussion in Special Features regarding Tropical Depression Thirteen. A weakening cold front is sagging south over the east-central Atlantic, from 31N30W to 29N38W to 31N45W. No convection is occurring with this front. To the west, high pressure of 1021 mb centered near 31N50W continues to dominate much of the basin. Fresh east winds are occurring off the north coast of Hispaniola, with moderate trades occurring in the Atlantic from 15N to 25N between 35W and 50W. Otherwise, light to gentle winds prevail. Farther east, fresh to strong northerly winds are off the coasts of Western Sahara and Mauritania. Seas range 4-7 ft. Tropical Depression Thirteen near 15.2N 49.8W 1008 mb at 5 AM EDT moving WNW at 18 kt. Maximum sustained winds 30 kt gusts 40 kt. Thirteen will move to 16.4N 52.7W this afternoon and strengthen to a tropical storm near 17.5N 56.4W Fri morning. The tropical storm will then reach near 18.4N 60.2W Fri afternoon, 19.1N 63.9W Sat morning, 19.8N 67.1W Sat afternoon, and 20.8N 71.0W Sun morning. Thirteen is forecast to remain a tropical storm as it passes near eastern Cuba and the southeastern Bahamas early Mon. $$ KONARIK