000 AXNT20 KNHC 192111 AAA TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 2111 UTC Mon Apr 19 2021 Updated Caribbean Sea section 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 2045 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea near 10N14W to 07N16W and to 04N20W. The ITCZ continues from 04N20W, to the Equator along 29W, and continuing along the Equator at 34W. Precipitation: widely scattered moderate to isolated strong in clusters is from 07N southward from 40W eastward. Isolated moderate to locally strong is elsewhere from 10N southward from 60W eastward. GULF OF MEXICO... A stationary front passes through 31N80W in the Atlantic Ocean, to 29N82W in Florida, curving into the central Gulf of Mexico near 26N90W, curving to 23N94W, and reaching the coast of Mexico near 19N95W. The stationary front continues northwestward in interior sections of Mexico to 24N100W. A surface trough is within 60 nm to 180 nm to the southeast of the stationary front. A second surface trough runs north-to-south, in the Yucatan Peninsula. Precipitation: widely scattered moderate to isolated strong is from 25N southward from 87W eastward. Isolated moderate is elsewhere from 28N southward from 88W eastward. A nearly stationary front extends from near Tampa Bay, Florida, to 25N92W, to the western Bay of Campeche. Fresh to strong winds, occurring to the west of this boundary in the southwestern Gulf of Mexico, will continue to diminish today. This front will remain nearly stationary into mid-week, before reinforcing cool and dry air pushes the front into the far southeastern Gulf of Mexico, from mid-to-late week. CARIBBEAN SEA...Updated The eastern Caribbean Ashfall Advisory ended this morning. Latest satellite analysis indicates that previous observed volcanic ash has dissipated, and no new volcanic ash is presently visible. Comparatively drier air in subsidence is apparent in water vapor imagery, from 66W eastward. An Atlantic Ocean upper-level trough passes through 13N55W, toward the eastern sections of Venezuela. The trough is surrounded by the comparatively drier air. Upper-level NW wind flow is moving toward Venezuela and Colombia, in general. An upper level anticyclonic circulation center is in Honduras. The GFS model for 500 mb shows: an anticyclonic circulation center that is near 24N61W in the Atlantic Ocean. Anticyclonic wind flow is covering the Caribbean Sea to the east of the line that runs from SW Haiti to the coast of Venezuela along 68W. The GFS model for 700 mb shows: an anticyclonic circulation center is near 26N61W in the Atlantic Ocean. Anticyclonic wind flow is covering much of the Caribbean Sea. Broad cyclonic wind flow covers the SW corner of the Caribbean Sea from 14N southward from 75W westward. The monsoon trough is along 11N73W in northern Colombia, across eastern Panama just to the north of the border with Colombia, beyond 07N84W, into the eastern Pacific Ocean. Precipitation: widely scattered moderate to isolated strong is within 150 nm to the west of the line that runs from 10N79W and to 15N84W in eastern Honduras. Broken to overcast low-level clouds, and isolated moderate rainshowers, cover the rest of the Caribbean Sea. The clouds and isolated moderate precipitation are moving with the surface to low-level wind flow. A ridge extends to the north of the basin, across the Atlantic Ocean, through the central Bahamas. The ridge will shift eastward, in advance of a weak front moving across the Gulf of Mexico. This will be allowing for trade winds to increase in mainly the south central Caribbean Sea, through mid-week. Looking ahead: The trade winds will diminish by late week, as the high pressure shifts eastward, although fresh to strong winds will persist off Colombia. ATLANTIC OCEAN... A stationary front passes through extends from a 1006 mb low pressure center that is near 32N76W to 31N81W to beyond 29N82W in Florida. Precipitation: scattered moderate to widely scattered strong is within 240 nm to the south and southeast of the 1006 mb low pressure center and stationary front, between 69W and 78W. Isolated moderate convection is elsewhere from 25N northward from 64W westward. A surface ridge extends from a 1026 mb high pressure center that is near 35N26W to 28N36W to 23N50W to 21N65W and to beyond the coast of Cuba near 23N78W. Surface anticyclonic wind flow covers the Atlantic Ocean away from the 31N81W-to-Florida 29N82W stationary front southeastward. The current weak frontal boundary will remain nearly stationary off the coast of northeastern Florida, through Tuesday night, as a ridge extends westward from the central Atlantic Ocean to the central Bahamas. The ridge will slide eastward on Wednesday, in response to a cold front that will move off the southeastern U.S.A. coast. The front will reach from near 31N74W to Stuart in Florida on Wednesday night, and from near Bermuda to the Straits of Florida by late Thursday. The front is forecast to begin to stall near 25N through Friday night, as high pressure builds between northeastern Florida and Bermuda. $$ mt/ja