000 AXNT20 KNHC 081721 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Mon Mar 8 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 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1200 UTC surface analysis and satellite imagery through 1630 UTC. ...SPECIAL FEATURES... Atlantic Gale Warning: A cold front extends from 32N60W to 27N63W to the Windward Passage. A post-frontal surface trough is from 31N63W to 27N66W. Recent ASCAT passes from 08/1312 and 08/1426 UTC reveal near gale to gale force NW winds north of 30N and within 90 nm to the W of the surface trough. Seas in the gale area are analyzed to currently be 12 to 16 ft. As the front moves eastward, expect gale conditions to lift N of the forecast area (N of 31N) by early this afternoon. Caribbean Gale Warning: Strong high pressure building behind a cold front moving SE across the western Atlantic will increase the pressure gradient across the south-central Caribbean through midweek. Winds within 90 nm of the coast of Colombia are expected to increase to gale force tonight, and then again Tue night. Seas will reach 12 ft or higher during the period of peak winds. Refer the High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details on the Gale Warnings. Heavy Rainfall in Hispaniola and Honduras: A cold front extending from the Windward Passage to the NW coast of Honduras will reach Hispaniola tonight and stall over the island through Tue evening. Heavy rainfall is forecast with the potential for localized flooding, particularly for northwestern portions of the Dominican Republic late tonight through Tue night. The tail end of the same front is stalling out over northern Honduras, where locally heavy rainfall is also likely through early Wed. See products issued by your National Meteorological Service for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough extends off the coast of Guinea near 11N15W to 04N18W. The ITCZ continues from 04N18W to 01N30W to the coast of Brazil near 01.5S45W. Scattered moderate convection is south of the monsoon trough from 01N-09N between 07W-18W. Scattered moderate convection is also seen within 120 nm either side of the ITCZ between 19W and the coast of South America. GULF OF MEXICO... Strong 1036 mb high pressure centered near Asheville North Carolina extends a ridge S into the Gulf which is currently supporting fresh winds over the eastern half of the basin and moderate NE to E winds W of 90W. A recent ASCAT pass shows strong NE to E winds over SE Gulf. Recent buoy observations from the SE Gulf support these winds and have also measured seas around 8 ft. Seas are estimated to currently be 6 to 9 ft in the SE Gulf and south-central Gulf, highest in the Florida Straits. In the northern and western Gulf, seas are 3 to 6 ft. Strong dry air subsidence continues to support mainly clear skies in the NE Gulf. Over the SW Gulf, shallow moisture is supporting areas of overcast low clouds with showers. Strong high pressure over the southeastern U.S. will support fresh to strong NE to E winds over the SE Gulf and the Florida Straits through midweek. As the ridge slides eastward during the latter parts of this week, fresh SE return flow will develop across much of the northern and western Gulf. CARIBBEAN SEA... Please see the Special Features section for details on the Gale Warning for the south-central Caribbean Sea and on the heavy rainfall for portions of Hispaniola and Honduras. A cold front extends from the Windward Passage to 19N79W. The front is stationary from 19N79W to the north coast of Honduras near 16N87W. Scattered showers are along portions of the front, including near the N coast of Haiti, near the N coast of Honduras, and just to the west of the Cayman Islands. Relatively dry conditions prevail across the eastern and central Caribbean. Scattered moderate tstorms are seen over portions of eastern Panama and adjacent waters south of 10.5N between 77W-82W. A recent ASCAT pass shows strong to near gale force NE winds to the north of the front, south of Cuba. The data shows moderate trades in the E Caribbean with fresh winds in the central Caribbean. However, strong NE winds are seen in the south-central to SW basin near the coasts of Colombia and eastern Panama. Seas is the NW Caribbean are averaging 6-8 ft. For the forecast, fresh to strong trade winds will persist across the south-central Caribbean through midweek, with gale-force winds expected to pulse off the coast of Colombia for the next several nights. Elsewhere, the front is forecast to stall from the Dominican Republic to Honduras tonight through Tue evening, bringing periods of heavy rain and potential flooding to northern Hispaniola as well as northern Honduras. The front will weaken over the next couple of days, but strong NE winds will persist north of the front into midweek over the NW Caribbean and through the Windward Passage, with locally near gale force possible from the Windward Passage to the Jamaica adjacent waters through Wed. Of note...a robust wet pulse of the Madden Julian Oscillation is currently generating numerous showers and tstorms over western Colombia. Periods of heavy rains are expected over western Colombia through early Tue. These rains are likely to cause localized flooding. Please refer to the forecasts of your local meteorological offices for more details. ATLANTIC OCEAN... A cold front extends from 32N60W to 27N63W to the Windward Passage. Satellite imagery shows scattered moderate convection along and within 120 nm SE of the front, north of 26N and east of 63W. Isolated showers are occurring along portions of the remainder of the front. A recent ASCAT pass reveals near gale force S-SW winds just ahead of the front, north of 28N. A post-frontal surface trough is analyzed from 31N63W to 27N66W. From 30N-31N, near gale force SW winds are between the front and the surface trough, while near gale to gale force NW winds are within 90 nm to the W of the surface trough. Please see the Special Features section for more details about the ongoing Gale Warning in this area. Fresh to strong northerly winds prevail elsewhere over the W Atlantic between the cold front and Florida, with seas 8-13 ft. For the forecast, the front will move eastward through tonight, reaching along 32N50W to 22N65W to the Dominican Republic early Tue. The portion west of 65W will stall on Tue and gradually dissipate through midweek. Strong high pressure will build behind the front and support fresh to strong N to NE winds with large seas in the 8-12 ft range much of this week, south of 27N between 60W and the Bahamas. The remainder of the basin is under the influence of the Azores High, currently at 1034 mb centered near 34N34W. The high is supporting a large area of fresh to strong trade winds from 05N-26N between 20W-53W. Seas in this area are 7 to 12 ft in primarily easterly trade wind swell. $$ Hagen