000 AXNT20 KNHC 251740 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 140 PM EDT Wed Oct 25 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 1200 UTC surface analysis and satellite imagery through 1715 UTC. ...TROPICAL WAVES... A tropical wave is E of the Lesser Antilles with axis extending from 19N56W to 13N59W to 07N59W, moving W at 5-10 kt. The wave is in an area of abundant moisture as depicted on SSMI TPW imagery. There is also a distinct 700 mb trough axis associated with this wave. Scattered moderate to isolated strong convection is within 120 nm of the wave axis. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 10N14W to 08N20W. The Intertropical Convergence Zone axis extends from 08N20W to 08N42W to 07N50W to 06N55W. Aside from the convection associated with the tropical wave, scattered moderate to isolated strong convection is from 03N-12N between 30W-42W, and from 08N- 13N between 42W-50W. ...DISCUSSION... GULF OF MEXICO... As of 1500 UTC a cold front is over the Straits of Florida from 24N80W to W Cuba at 23N81W. Scattered showers are within 60 nm of the front. A 1029 mb high is centered over N Mexico near 27N102W. The surface pressure gradient between this high and the cold front is rather tight thus 20-25 kt northerly winds are over the Gulf of Mexico. Mostly fair weather is over the remainder of the Gulf. S Mexico S of 21N to the base of the mountains, has overcast low clouds and showers. In the upper levels, a large upper level trough is over the Gulf with axis along 85W supporting the frontal system now mostly over the W Atlantic. Expect in 24 hours for the surface high to move to the NW Gulf of Mexico, with fair weather and weaker surface winds. CARIBBEAN SEA... As of 1500 UTC, a cold front extends from W Cuba near 23N81W to 20N86W to the Gulf of Honduras near 16N88W. Widely scattered moderate convection is over the NW Caribbean from 16N- 21N between 82W-88W. A surface trough extends from 20N79W to a 1008 mb low off the coast of Nicaragua near 12N82W. Scattered moderate to strong convection is from 10N-17N between 78W-84W. Further E, a tropical wave is approaching the Lesser Antilles, see above. Of note in the upper levels, an upper level ridge is over the NW Caribbean and Central America. A small upper level low is centered over the E Caribbean near 13N63W. Upper level diffluence E of the low is enhancing the convection E of the Lesser Antilles. Expect the surface low off the coast of Nicaragua to remain quasi-stationary for the next 24 hours with continued convection. Also expect the tropical wave to gradually move into the E Caribbean with convection mostly E of the wave axis. ...HISPANIOLA... Dry air northerly flow aloft will support fair weather across the island through Thursday. Moderate trades are also expected to persist. ATLANTIC OCEAN... A cold front is over the W Atlantic from 31N76W to the Straits of Florida near 24N80W. Scattered moderate convection is within 120 nm E of the front. A cold front is over the central Atlantic from 31N29W to 25N40W to 25N46W. Scattered showers are within 90 nm of the front. Of note in the upper levels, an upper level low is centered over the central Atlantic near 29N59W. Widely scattered moderate convection is from 26N-29N between 51W-57W. Expect the two fronts to move E over the next 48 hours with convection. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa