000 AXNT20 KNHC 300005 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 705 PM EST Fri Dec 29 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 passes through the coastal areas of Liberia near 05N09W to 06N16W and 05N21W. The ITCZ continues from 05N21W to 04N25W 04N30W 03N38W 05N49W, and 05N52W at the coast of French Guiana. Precipitation: widely scattered moderate to isolated strong from 04N to 08N between 41W and 51W, and from 10N southward between 55W and 60W. isolated moderate elsewhere from 02N to 05N between southern sections of Liberia and 30W, and elsewhere from 11N southward between 30W and 60W. ...DISCUSSION... ...THE GULF OF MEXICO... A stationary front extends from 27N81W in Florida just to the north of Lake Okeechobee, into the central Gulf of Mexico, to a 1022 mb low pressure center that is near 26N95W, to 20N97W along the coast of Mexico, and curving NW into Mexico, beyond the Texas Big Bend. A surface trough, also, is along 26N85W 24N88W 23N91W. Broken to overcast low level clouds, and a mixture of fog at some oil platform sites, mist, and possible rainshowers, are to the north of the line from the Florida Keys, to 22N90W, to 20N96W in the SW corner of the Gulf of Mexico. ...THE CARIBBEAN SEA... Upper level W-to-SW wind flow is moving across Trinidad. Scatterometer winds for the surface are from the northeast. The GFS model forecast for the next 48 hours, shows that an upper level ridge will be across the area, on top of a 500 mb-to-700 mb inverted trough. scattered to broken low level clouds and rain are being observed in Trinidad and Tobago, and in the surrounding areas from 15N southward from 71W eastward. The 24-hour rainfall total in inches, for Trinidad, for the period that ended at 29/1200 UTC, according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...is 3.09 inches. Scatterometer winds are from the NE from 17N southward from 77W eastward to Central America. A surface trough extends from the central coast of Panama to SE Nicaragua. Precipitation: isolated to widely scattered moderate rainshowers cover the area from 16N southward from 79W westward, reaching the coastal plains/interior sections, mostly in Nicaragua at the present time. A surface trough is in the NW corner of the Caribbean Sea. Precipitation: isolated moderate rainshowers are from 21N southward from 82W westward. Broken low level clouds and possible rainshowers also are from 13N to 17N between 73W and 78W. 24-hour rainfall totals in inches, for the period that ended at 29/1200 UTC, according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are: 3.09 in Trinidad, 0.19 in San Juan in Puerto Rico, 0.16 in St. Thomas in the Virgin Islands, and 0.02 in Guadeloupe. ...HISPANIOLA... SURFACE OBSERVATIONS...Scattered to broken low level clouds and possible rainshowers are from 16N to 20N between 66W and 69W, between Puerto Rico and the Mona Passage, and from 17N to 24N between 69W and 75W, from Hispaniola into the SE Bahamas. Rain is being reported in Santo Domingo in the Dominican Republic. Earlier reports showed rain in the Dominican Republic: in Punta Cana and in Santiago. The GFS MODEL forecast for 250 mb shows that SW-to-W wind flow will move across the island during the next 2 days. A ridge will extend from the SE corner of the Caribbean Sea to eastern Honduras. The GFS MODEL forecast for 500 mb shows that day one will start with a ridge from the SE corner of the Caribbean Sea to Hispaniola. The ridge will shift eastward, pushing SW wind flow across Hispaniola for the next 36 hours or so. Day two will end with a mixture of W-to-NW wind flow across the area. The GFS MODEL forecast for 700 mb shows that day one will consist of an anticyclonic circulation center being 130 nm to 160 nm to the north of Hispaniola. NE wind flow will move across the area during the first half of the day. An inverted trough will move into the area during the second half of day one. The inverted trough will remain across Hispaniola during all of day two, bringing with it cyclonic wind flow. ...THE ATLANTIC OCEAN... A cold front passes through 32N48W to 27N59W. The front becomes stationary, and it continues from 27N59W to 27N64W and 28N67W. The front becomes warm from 28N67W to 31N74W, and to a 1018 mb low pressure center that is near 30N77W. A cold front continues from the 1018 mb low pressure center, to the Florida coast near 25N80W. A surface trough is along 27N53W 23N57W 19N60W. Precipitation: isolated moderate rainshowers to the NW of 32N40W 15N60W. An upper level trough extends from 31N26W to 22N35W, to 15N44W. A surface trough is along 27N32W 24N35W 21N36W. Rainshowers are possible from 20N to 27N between 27W and 36W. For additional information please visit http://www.hurricanes.gov/marine $$ MT