000 AXNT20 KNHC 151741 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 141 PM EDT Sun Apr 15 2018 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 1730 UTC. ...SPECIAL FEATURES... ...Atlantic Gale Warning... A cold front will move across the west Atlantic area extending from 31N77W to 27N80W by early Mon. Gale-force winds are expected north of 29N between 75W-78W, with seas ranging between 10-12 ft. These conditions will diminish by Mon afternoon. For more details, please refer to the High Seas Forecast under AWIPS/WMO headers HSFAT2/FZNT02 KNHC. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of western Africa near 07N13W to 04N20W. The ITCZ continues from 04N20W to 02N50W near the mouth of the Amazon River. Scattered moderate convection is observed within 190 nm of the monsoon trough and ITCZ between 14W and 45W. ...DISCUSSION... GULF OF MEXICO... Strong winds follow a late season cold front that extends from 30N86W to 21N90W. A pre-frontal trough 29N84W to 24N87W. Scattered to numerous showers and thunderstorms along with gusty winds are noted with the trough and front affecting the eastern portion of the basin mainly east of 89W, including the Yucatan Peninsula and Channel. Seas will range between 8-12 ft near the front. A surface ridge is building in the wake of the front anchored by a 1023 mb high centered over northeast Mexico near 24N99W. The front will continue moving east across the area through tonight. Winds and seas diminish into Mon as high pressure builds across the basin and persists through mid week. Fresh to strong SE return flow will set up over the northwest Gulf by late Tue between the ridge and lower pressure over the southern Plains. A weaker cold front is forecast to stall and dissipate over the northern Gulf Thu. CARIBBEAN SEA... Moderate to fresh easterly winds prevail across most of the basin. Recent scatterometer passes indicate fresh to strong east winds off northeast Colombia and near the Gulf of Honduras. Seas over the south central Caribbean are likely 8 to 10 ft, with 5 to 8 ft elsewhere. A recent altimeter satellite pass showed NE to E swell over the tropical Atlantic has largely decayed below 8 ft. No significant convection is observed at this time. The cold front currently over the eastern Gulf will enter the northwest Caribbean late today, and stall from central Cuba to central Honduras by early Mon, before dissipating through late Tue. A surface trough has developed over the eastern coast of the Yucatan Peninsula ahead of the front with scattered moderate convection. This activity will continue as the front moves through the basin. The strong east winds off Honduras will diminish as the ridge north of the area shifts eastward ahead of the front. But strong NW winds will follow the front from the coast of Quintana Roo to the Gulf of Honduras, before diminishing Mon. Elsewhere, the fresh to strong trade winds will continue to pulse near the coast over the south central Caribbean through mid week. ATLANTIC OCEAN... Gale-force winds are expected to develop over the west Atlantic by early Mon. Please refer to the section above for more details. High pressure northeast of the area is supporting pulses of fresh to strong trade winds off Hispaniola, as noted in recent scatterometer imagery and ship observations. The strong winds are noted mainly along the northern coast of Haiti as far west as the approaches to the Windward Passage. Southeast winds are starting to increase to fresh to strong mainly west of 75W ahead of a cold front that will move off the northeast Florida coast this afternoon, then increase to gale- force west and east of the front north of 29N by early Mon. Winds will diminish by Mon afternoon as the front moves east and reaches from 30N72W to central Cuba, then from Bermuda to eastern Cuba by late Tue, then lifting north to 25N and dissipating through mid week. Elsewhere, surface ridging prevails across the basin anchored by a 1030 mb high near 33N58W and a 1028 mb high near 28N40W. A stationary front extends in between these high centers from 31N40W to 29N54W. The ridge is maintaining light winds north of 20N, with moderate to fresh trade winds south of 20N. East swell of 7 to 9 ft persists south of 20N as well, as noted in recent altimeter satellite passes, reaching as far west as the Windward Islands. The stationary front will dissipate today, and the ridge will shift east Mon ahead of a reinforcing front that will move into the region Tue. The front will slide east of 35W Wed, followed by a large area of NW swell with wave heights of 8 to 10 ft covering much of the area north of 20N and east of 45W Wed and Thu as the swell in excess of 8 ft south of 20N will subsides. For additional information please visit http://www.hurricanes.gov/marine $$ ERA