000 AXNT20 KNHC 270556 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Fri Aug 27 2021 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0530 UTC. ...SPECIAL FEATURES... The center of Tropical Storm Ida, at 27/0600 UTC, is near 19.4N 80.9W. This position also is about 27 nm/50 km to the ENE of Grand Cayman, and about 270 nm/500 km to the ESE of the NW tip of Cuba. IDA is moving NW, or 320 degrees, 10 knots. The estimated minimum central pressure is 1006 mb. The maximum sustained wind speeds are 35 knots with gusts to 45 knots. The maximum sea heights are reaching 10 feet. Precipitation: scattered to numerous strong are within 260 nm of the center in the E semicircle. Hurricane watches have been announced for parts of the U.S.A. coast in the northern Gulf of Mexico. Please, read the latest NHC Public Advisory, at https://www.nhc.noaa.gov/text/MIATCPAT4.shtml, and the Forecast/Advisory at https://www.nhc.noaa.gov/text/MIATCMAT4, for more details. Please, refer to the NHC High Seas Forecasts, at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for marine impacts. A 1014 mb low pressure center is near 32N54W, about 550 nm to the E of Bermuda. Precipitation: Scattered to numerous strong is within 45 nm of the center in the E semicircle, and within 90 nm of the center in the W semicircle. Isolated moderate to locally strong is within 210 nm of the center in the N semicircle, and within 240 nm of the center in the S semicircle. The environmental conditions are forecast to be generally conducive for development. It is likely for a tropical depression to form during the weekend. The system is expected to move eastward slowly during the next day or two, with a faster northeastward motion forecast to begin on Sunday. The formation chance through 48 hours is medium. A tropical wave is along 43W/44W, from 18N southward, moving westward 10 to 15 knots. A 1008 mb low pressure center is along the tropical wave near 12.5N. Precipitation: widely scattered moderate to isolated strong is within 300 nm of the center in the W quadrant. Scattered to numerous strong is from 370 nm to 470 nm of the center in the NE quadrant, and from 260 nm to 370 nm of the center in the SE quadrant. Isolated moderate to locally strong is elsewhere within 540 nm of the center. Gradual development of this system is expected. It is likely for a tropical depression to form during the next couple of days, before it moves into an environment of stronger upper level winds and slightly cooler waters. The disturbance is forecast to move west-northwestward for another day or so, and then turn northward during the weekend. The formation chance through 48 hours is medium. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 23W/24W, from 18N southward, moving westward 10 knots. Precipitation: isolated moderate to locally strong is from 05N to 10N between Africa and 33W. A Caribbean Sea tropical wave is along 61W/62W, from 19N southward, moving westward 10 to 15 knots. Precipitation: isolated moderate is within 150 nm on either side of the tropical wave. A Caribbean Sea tropical wave is along 82W/83W, from 15N southward, moving W 5 to 10 knots. Precipitation: scattered moderate to isolated strong is within 135 nm to the west of the tropical wave, from 08N to 10N, in Panama and in Costa Rica, and in the coastal waters. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Senegal near 14N17W, to 09N23W, to 14N30W, 14N35W, through the 1008 mb low pressure center that is along the 43W/44W tropical wave, to 06N49W. The ITCZ continues from 06N49W to the coast of French Guiana along 53W/54W. Precipitation: isolated moderate is elsewhere to the south of the line that runs from 20N16W to 20N50W to 13N60W to 10N62W. GULF OF MEXICO... Upper level anticyclonic outflow, that is curving away from the NW Caribbean Sea Tropical Storm IDA, is reaching Florida near 29N, and curving toward 29N70W in the Atlantic Ocean. Upper level cyclonic wind flow covers the rest of the Gulf of Mexico that is away from the T.S. IDA outflow, from 90W eastward. A surface trough is along 18N86W in the NW Caribbean Sea, through the Yucatan Channel, to 25N87W and 30N87W at the Florida Panhandle. Precipitation: widely scattered moderate to isolated strong is within 100 nm on either side of the trough in the Gulf of Mexico. Isolated moderate to locally strong is within 150 nm on either side of the trough, from the Yucatan Peninsula and the Yucatan Channel southward, into the NE Caribbean Sea. Upper level anticyclonic wind flow covers the Gulf of Mexico from 22N northward from 90W westward. Precipitation: isolated moderate covers the area of upper level anticyclonic wind flow. Tropical Storm Ida near 18.6N 80.5W 1006 mb at 11 PM EDT moving NW at 10 kt. Maximum sustained winds 35 kt gusts 45 kt. Ida will move to 19.9N 82.0W Fri morning, 21.8N 83.9W Fri evening, strengthen to a hurricane near 23.8N 85.9W Sat morning, 25.6N 88.0W Sat evening, 27.3N 89.6W Sun morning, and 29.0N 90.6W Sun evening. Ida will weaken to a tropical storm while moving inland over 32.0N 91.0W by late Mon. CARIBBEAN SEA... The center of Tropical Storm IDA is in the NW corner of the Caribbean Sea. The maximum sea heights are reaching 10 feet. Precipitation: scattered to numerous strong are within 260 nm of the center in the E semicircle. Hurricane watches have been announced for parts of the U.S.A. coast in the northern Gulf of Mexico. The SPECIAL FEATURES section has more detailed information about Tropical Storm Ida. The eastern extension of the eastern Pacific Ocean monsoon trough is along 10N/11N from 74W in Colombia, beyond Costa Rica, and into the eastern Pacific Ocean. Precipitation: numerous strong is within 120 nm to the south of the monsoon trough between 73W and 77W. Widely scattered moderate to isolated strong is within 120 nm to the north of the monsoon trough between 73W and 77W. Tropical Storm Ida near 18.6N 80.5W 1006 mb at 11 PM EDT moving NW at 10 kt. Maximum sustained winds 35 kt gusts 45 kt. Ida will move to 19.9N 82.0W Fri morning, 21.8N 83.9W Fri evening, strengthen to a hurricane near 23.8N 85.9W Sat morning, 25.6N 88.0W Sat evening, 27.3N 89.6W Sun morning, and 29.0N 90.6W Sun evening. Ida will weaken to a tropical storm while moving inland over 32.0N 91.0W by late Mon. Moderate to fresh winds are expected elsewhere through the forecast period, except for locally strong winds in the south central Caribbean Sea through the weekend. ATLANTIC OCEAN... Upper level anticyclonic outflow, that is curving away from the NW Caribbean Sea Tropical Storm IDA, is reaching Florida near 29N, and curving toward 29N70W in the Atlantic Ocean. A surface trough is along 29N64W, 25N66W, 22N69W. Precipitation: isolated moderate to locally strong is within 275 nm to the west and northwest of the surface trough, and within 210 nm to the east of the surface trough from 27N northward. A surface trough passes through 31N22W, to 30N25W 29N29W 27N30W 23N32W. Precipitation: rainshowers are possible within 210 nm to the north and northwest of the trough from 30W eastward, and from 20N northward between 30W and 44W. High pressure, that is just to the N of the forecast region, will dominate the SW N Atlantic Ocean through Monday, supporting gentle to moderate E to SE winds. Fresh winds are expected to pulse to the N of Hispaniola during the evening hours through Saturday night. A low pressure center is forecast to develop to the E of the Bahamas by early next week. $$ mt/era