000 AXNT20 KNHC 132347 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 747 PM EDT Thu Apr 13 2017 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across the western Africa coast near 09N13W to 06N15W. The Intertropical Convergence Zone continues from 06N15W to 03N25W to 02S44W. Isolated moderate convection is south of 02N between 17W and 28W. ...DISCUSSION... ...THE GULF OF MEXICO... A ridge, anchored by a high pressure system located NE of the area, continues to dominate the Gulf region. Under the influence of this system, a moderate to fresh E to SE flow prevails. A thermal trough will develop over the Yucatan Peninsula each evening, then move westward into the SW Gulf overnight where it will dissipate each morning. A surge of fresh to occasionally strong NE winds will accompany this trough through the weekend. Some cloudiness, with likely embedded showers, is noted over the NW and north- central Gulf, and along the coast of Mexico, mainly north of Tuxpan. A patch of low level moisture is also seen over the SE Gulf under an easterly wind flow. A ridge will persist across the Gulf the remainder of the week into the weekend, with little change in the weather pattern. CARIBBEAN SEA... High pressure north of the region supports moderate to fresh easterly trades over the majority of the Caribbean Sea. The only exceptions are fresh to locally strong winds along the northwestern coast of Colombia, and in the Windward Passage. The most recent scatterometer data confirmed the presence of these winds. A surface trough extends from the Atlantic and across the US Virgin Islands. This trough has been drifted eastward since yesterday. The San Juan Doppler Radar shows scattered showers in association with this trough. Abundant tropical moisture, combined with the local effects, is helping to induce convection over parts of Puerto Rico. Patches of low level moisture, embedded in the trade wind flow, are noted across the remainder of the basin. The above mentioned trough continues to disrupt the trade wind flow over the northeastern Caribbean. Fresh winds near the coast of Colombia will pulse to strong each night through Monday. Gentle to moderate trade winds are expected elsewhere through early Saturday. Winds are forecast to increase to a fresh breeze on Sunday as high pressure builds north of the area. ...HISPANIOLA... A typical weather pattern for this time of the year will prevail across the island over the next couple of days, with mainly isolated showers and thunderstorms due to local effects. ATLANTIC OCEAN... A low pressure system of 1011 mb continues to spin east of the Bahamas. At 13/1800 UTC, the center is located near 25N67W. The pressure gradient between this low and a high pressure located near 36N60W is producing a large area of fresh to strong winds within about 360 nm north semicircle of the low center. The low is forecast to meander over this area through tonight, then shift NE on Friday. High pressure will build in the wake of this departing low pressure through this weekend bringing an increase in winds and seas across the western Atlantic on Saturday, then across the central Atlantic on Sunday. A cold front enters the forecast area near 31N32W, and continues SW to 25N50W where it transitions to a stationary front to 28N65W, then transitions again to an occluded front to 28N68W to 25N71W. The aforementioned low pressure is centered south of the occluded front. Mainly low clouds are associated with the low. A 1023 mb high centered just E of the Madeiras Islands dominates the remainder of the central Atlantic and the eastern Atlantic. For additional information please visit http://www.hurricanes.gov/marine $$ GR