000 AXNT20 KNHC 272335 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 635 PM EST Wed Dec 27 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 2330 UTC. ...ITCZ/MONSOON TROUGH... The monsoon trough enters the Atlantic Ocean along 04N through 10W. The Intertropical Convergence Zone extends from 04N10W to 04N34W to 00N50W. Scattered moderate convection is from 03N-10N between 28W-42W. ...DISCUSSION... GULF OF MEXICO... A weak 1020 mb low pressure persists across the north-central Gulf and now is located near 28N88W. A cold front extends southwest from the low to 25N97W. A warm front extends eastward from the low to 28N83W then transitions into a cold front and extends across the Florida Peninsula. The pressure gradient between the low/front and strong high pressure north of the area is resulting in fresh to strong northeast winds behind the frontal boundary, while gentle to moderate southeasterly winds prevail south of the front. Moderate to locally fresh northeasterly winds are depicted in scatterometer data near the Yucatan Peninsula likely associated with a thermal trough. The low/fronts will dissipate during the next 24 hours. High pressure will build in in the wake of the front. Looking ahead, the next strong cold front is expected to emerge off the Texas and Louisiana coasts Sunday evening followed by strong to gale-force winds and building seas of up to 14-15 ft by early next week. CARIBBEAN SEA... The most recent scatterometer data show moderate to fresh winds over the central Caribbean and eastern Caribbean, and gentle to moderate winds over the western Caribbean. Patches of low-level moisture embedded in the trade wind flow are producing isolated to scattered passing showers across the Greater and Lesser Antilles from time to time. Little change in this weather pattern is expected during the next couple of days. Expect strong to near- gale force nocturnal winds near the coast of Colombia tonight. Strong northeast winds are then expected along the coast of Colombia during the overnight and early morning hours through the upcoming weekend. East swell currently across the tropical Atlantic waters, including the east Atlantic passages, will begin to subside from the during the next 24 hours. ...HISPANIOLA... Isolated to scattered showers carried by the trade winds will continue to affect the island from time to time. Mostly dry and stable conditions are expected to persist during the next couple of days under the influence of a mid to upper-level ridge and associated strong subsidence. A larger patch of moisture may cross the island Thursday night into Friday, slightly increasing the likelihood of showers. ATLANTIC OCEAN... A 1020 mb surface low is centered north of the area. A frontal system extends across the west Atlantic, analyzed as a cold front from 31N77W to 28N81W. To the east, this low is also extending a weakening stationary front across 31N between 60W-70W. No significant convection is related to any of these features at this time. The remainder of central and eastern Atlantic is under the influence of a surface ridge anchored by a 1031 mb high centered S of the Azores near 34N28W. The pressure gradient between this high and lower pressure in the vicinity of the ITCZ/monsoon trough is resulting in a large area of fresh to strong winds between the coast of Africa and the Lesser Antilles, with seas of up to 11-12 ft. The high pressure will move east and weaken some over the next 24 hours. For additional information please visit http://www.hurricanes.gov/marine $$ ERA