000 AXNT20 KNHC 262320 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Thu May 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...TROPICAL WAVES... A tropical wave is analyzed along 14W S of 12N. Scattered moderate and isolated strong convection is noted near the southern end of the wave axis south of 05N between 13W to 17W. A surface trough associated with the wave was noted in the scatterometer data. The Hovmoller Diagram shows the westward propagation of the wave. A second tropical is along 31N S of 11N, moving W around 15-20 kt. Scattered moderate convection is noted where the wave meets the ITCZ. The wave has no significant surface component and is analyzed based upon GFS-based 700 mb tropical wave diagnostics. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coast of Guinea Bissau near 12N16W to 05N20W. ITCZ extends from 05N20W to 04N28W, breaks for a tropical wave, then continues again from 04N33W to 04N52W along the coast of French Guiana. Scattered moderate and isolated strong convection is noted south of 05N between 13W and 17W, from 02N to 05N between 17W and 28W, and within about 150 nm N of the ITCZ. GULF OF MEXICO... A ridge dominates the Gulf waters producing mainly gentle to moderate E to SE winds. Moderate easterly winds prevail across the Straits of Florida. Seas are 1-3 ft over the NE Gulf and 3-5 ft elsewhere. Only a few showers are noted across the basin and a band of high clouds extending across central Mexico into the southern Gulf. Gentle to moderate east to southeast winds are expected through Sat night as weak high pressure off the NE Florida coast extends westward to SE Texas and gradually weakens. Fresh northeast to east winds will pulse nightly to strong off the Yucatan Peninsula tonight through Sat. A cold front is expected to move across the northern Gulf on Sat night into Sun and stall across the northern Gulf Sun night. Expect moderate north to northeast winds behind the front. CARIBBEAN SEA... A moderate pressure gradient between a 1025 mb high pressure located off NE Florida and the Colombian low is contributing to fresh to strong NE to E trades over the south-central Caribbean based on latest satellite derived wind data. Elsewhere, moderate to fresh trades prevail with the exception of gentle to moderate winds in the NW Caribbean. Shallow moisture embedded in the trade winds flow is noted across the area with some convective activity, mainly due to local effects, across parts of the Greater Antilles. Scattered showers and thunderstorms are occurring south of 12N in the SW Caribbean associated with the Pacific monsoon trough that extends from Costa Rica to northern Colombia. This convective activity is affecting parts of Panama and Costa Rica. Seas are 7-10 ft in the S central Caribbean and 4-7 ft elsewhere. Fresh to strong trades will prevail across the central portions of the Caribbean through early Thu as high pressure resideS offshore of the NE Florida coast. Winds will diminish significantly Thu through early next week as the high collapses. Fresh winds are expected to pulse to strong in the southern Gulf of Honduras and the Windward Passage tonight. ATLANTIC OCEAN... Two tropical waves are moving westward across the tropical Atlantic. Refer to the Tropical Waves section above for details. Ridging from a 1030 mb Bermuda-Azores High centered at 38N45W extends east-west north of our waters. A 1025 mb high pressure is located just off NE Florida while another high pressure center of 1025 mb is centered near 30N39W. A weak low pressure of 1022 mb is just E of Bermuda. A surface trough stretches from the low center to 28N66W to 27N71W. This trough is associated with a vigorous upper-level trough that extends southward across Hispaniola into the Caribbean Sea. Scattered showers are near the trough axis N of 28N. Moderate to fresh trades are noted roughly S of 15N and W 30W, with an area of 20-25 kt winds N of the ITCZ to about 12N between 45W and 50W where seas are 8 to 9 ft. Fresh to strong northerly winds are from 18N to 24N between the W coast of Africa and 20W. Seas are also in the 8 to 9 ft range within this area of winds. In the forecast for west of 65W, light winds will prevail north of 24N through Thu as weak low pressure just east of Bermuda interrupts the Atlantic ridge. Moderate to locally fresh winds will continue across the Bahamas and Greater Antilles through early Thu. Winds will become gentle to moderate Thu through Sun as the Atlantic ridge extends from the east central Atlantic weakly W-SW to Florida. Fri night, moderate to fresh southerly winds will develop off the NE Florida coast ahead of a cold front forecast to come off the southeastern CONUS early Sun. The cold front will move across northern Florida on Sun before stalling Sun night. In the forecast for east of 65W, the Bermuda-Azores High will weaken some on Thu leading toward a reduction in the NE to E trades to moderate to fresh. Seas should diminish across the waters below 8 ft by Fri. $$ GR