000 AXNT20 KNHC 070933 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 533 AM EDT Mon Sep 7 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 0900 UTC. ...SPECIAL FEATURES... Tropical Depression Seventeen is centered near 17.3N 42.1W at 07/0900 UTC or 1040 nm W of the Cabo Verde Islands moving WNW at 5 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Numerous moderate and scattered strong convection is noted within 180 nm in the NE semicircle and 30 nm in the SW semicircle. The depression is moving toward the WNW and this motion is expected to continue for the next few days with a gradual increase in forward speed. Some slow strengthening is forecast over the next few days, and the depression is expected to become a tropical storm later today. Please read the latest NHC Public Advisory at: https://www.nhc.noaa.gov/text/MIATCPAT2.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT2.shtml for more details. Tropical Depression Eighteen is centered near 15.2N 20.3W at 07/0900 UTC or 220 nm ESE of the Cabo Verde Islands moving W at 10 kt. Estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Numerous moderate and scattered strong convection is noted within 240-300 nm in the NW semicircle. The depression is moving toward the W and this general motion with some increase in forward speed is expected over the next few days. On the forecast track, the center of the cyclone is forecast to pass near or over the Cabo Verde Islands later today and tonight, and is expected to produce 2 to 5 inches of rain across portions of the Cabo Verde Islands through Tue. Gradual strengthening is forecast during the next 48 hours, and the depression is forecast to become a tropical storm later today or tonight. 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/MIATCMAT3.shtml for more details. ...TROPICAL WAVES... A tropical wave axis is near 20W from 03N-21N along Tropical Depression Eighteen. Convection and movement is described above. A tropical wave axis is near 64W/65W from 20N southward across the Anegada Passage to the N central coast of Venezuela, moving W at 20 kt. No significant convection is noted over land, however there is scattered moderate and isolated strong convection near the wave axis over Venezuela. A tropical wave axis is near 76W from the S coast of Cuba and near Jamaica to Colombia, moving W at 10 kt. Scattered moderate and isolated strong convection is noted from 16N-20N between 76W-79W, and within 90 nm NW of the coast of Colombia with additional activity over land N of 08N. A tropical wave axis is near 94W across the Isthmus of Tehuantepec southward into the east Pacific Ocean, moving W at 10 kt. Scattered moderate and isolated strong convection is noted S of 20N and E of 94W with additional activity inland over Mexico. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Senegal at 15N17W to Tropical Depression Eighteen to 18N37W then resumes W of Tropical Depression Seventeen to 11N50W. The ITCZ continues from 11N50W to near the border of Guyana and Brazil at 08N60W. Scattered moderate and isolated strong convection is noted from 17N-19N between 34W-36W. Scattered moderate convection is noted from 11N-13W between 16W-20W, within 120 nm SW of the monsoon trough between 24W-30W, from 12N-14N between 35W- 40W, and from 09N-11N between 47W-50W. GULF OF MEXICO... A stationary front extends across the northern Florida Peninsula. A surface trough is in the SW Gulf from 24N97W to 19N94W. Scattered moderate and isolated strong convection is noted W of the trough. Otherwise, broad high pressure is building across the basin from the Carolinas with mainly gentle to moderate easterly flow across the basin. Seas are mainly 3 ft or less across the NE half of the Gulf, and 3-4 ft across the SW half of the Gulf. The trough over the SW Gulf will linger today before dissipating. A weak cold front may dip into the northern Gulf by mid-week before dissipating. Overall gentle to moderate flow is expected to continue through the week. CARIBBEAN SEA... High pressure prevails N of the basin. Moderate to fresh winds prevail over the central Caribbean. Gentle to moderate winds prevail over the eastern Caribbean. Gentle winds prevail across the western Caribbean except moderate easterly winds S of 18N in the Gulf of Honduras. Seas are mainly 2-4 ft across the basin, except locally 5 ft in the central portion. Tropical Depression Seventeen will remain well E of the area through much of the week, but is forecast to reach near 20.6N 52.7W early Fri as a tropical storm and then near 21.7N 55.5W early Sat. Otherwise, a tropical wave S of eastern Cuba across Jamaica to Colombia will move across the western Caribbean through Tue and move out of the basin Tue night while a second tropical wave moves from the eastern Caribbean into the central forecast waters. Gentle to moderate trades will prevail across the basin through the week, occasionally and locally moderate to fresh in the S central Caribbean. ATLANTIC OCEAN... Refer to the Special Features section above for details on Tropical Depression Seventeen and Tropical Depression Eighteen. A stationary front extends across the Florida Peninsula NE off the N Florida coast. Scattered moderate convection is noted within 90 nm SE of the front. A 1011 mb low pressure is near 30N65W along NW to SE trough which reaches to 27N. Scattered moderate convection is noted from 26N-28N between 63W-67W. A ridge of high pressure extends from NW to SE through 26N72W with mainly moderate E-SE winds SW of the ridge, and gentle winds NE of the ridge except stronger winds near the low pressure area on the NE side. Isolated convection is also noted from the Central Bahamas westward through the Straits of Florida associated with a tropical upper tropospheric trough (TUTT), which is currently located near South Florida. The TUTT is forecast to linger in the vicinity of South Florida for much of the week. Tropical Depression Seventeen will remain well E of the area through much of the week, but is forecast to reach near 20.6N 52.7W early Fri as a tropical storm and then near 21.7N 55.5W early Sat. Elsewhere, a stationary front off the NE Florida coast will dissipate through today. Weak low pres near 30N65W will drift W through the week. Mainly gentle to moderate flow will prevail across the basin through the week. $$ Lewitsky