000 AXNT20 KNHC 270604 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 205 AM EDT TUE SEP 27 2016 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...SPECIAL FEATURES... An Atlantic Ocean tropical wave is along 50W/51W from 17N southward. Convective precipitation: scattered strong from 13N to 16N between 46W and 52W. Environmental conditions remain conducive for development. It is possible that a tropical depression may develop during the next day or two. This system is moving westward to west-northwestward about 20 mph. Please monitor the progress of this weather system if you have any interests that are in the eastern and central Caribbean Sea, including the northern coast of South America. Heavy rains and strong gusty winds, possibly to tropical storm force, are expected to spread across the Windward Islands and sections of the southern Lesser Antilles beginning late Tuesday or Wednesday. An Air Force Hurricane Hunter aircraft is scheduled to investigate this disturbance on Tuesday afternoon. The chance of formation during the next 48 hours is high. Gale wind conditions are forecast in 24 hours, within 120 NM N semicircle of the low center, and sea heights are forecast to range from 10 feet to 14 feet. Please refer to the HIGH SEAS FORECAST... MIAHSFAT2/FZNT02 KNHC for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 18W/19W from 19N southward, moving westward 10 to 15 knots. Convective precipitation: rainshowers are possible from 10N to 20N between Africa and 25W. A Caribbean Sea tropical wave is to the south of 19N, passing through the Mona Passage to 15N69W, and to 10N69W in NW Venezuela. Convective precipitation: isolated moderate from 15N to 20N between 66W and 70W. An upper level trough extends from an Atlantic Ocean 25N69W cyclonic circulation center, to Puerto Rico, into the Caribbean Sea, and toward Lake Maracaibo in NW Venezuela. Convective precipitation: isolated moderate from 20N southward between 60W and 70W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through coastal sections of Guinea near 10N14W, to 07N20W, to 09N35W, 08N41W, 10N48W and 10N54W. Convective precipitation: scattered strong from 11N to 12N between 33W and 39W. widely scattered moderate to isolated strong from 04N to 08N between 27W and 33W. isolated moderate elsewhere from 13N southward from 42W eastward. ...DISCUSSION... ...THE GULF OF MEXICO... An upper level cyclonic circulation center is in the NE corner of the Gulf of Mexico, near 29N83W, just to the south of Cedar Key in Florida. Upper level cyclonic wind flow covers much of the Gulf of Mexico that is from 90W westward. A surface trough extends from 31N80W, to just to the west of Lake Okeechobee in Florida. Convective precipitation: isolated moderate from 86W eastward. in the Atlantic Ocean: scattered moderate to isolated strong from 26N to 30N between 70W and 73W, and within a 30 nm to 60 nm radius of 29N75W. isolated moderate from 20N northward from 70W westward. Upper level anticyclonic wind flow covers the rest of the Gulf of Mexico. An upper level ridge cuts through Texas along a NW-to- SE line, and then across the western sections of the Gulf of Mexico. A surface trough is along 95W/96W from 28N southward. Convective precipitation: scattered moderate to strong from 20N to 22N between 95W and 96W. isolated moderate covers the rest of the area that is from 90W westward. scattered strong in central Guatemala, and in Mexico between Guatemala and the Isthmus of Tehuantepec. ...FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N NORTHWARD AND FROM 88W WESTWARD... LIFR: none. IFR: none. MVFR: KEHC. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... TEXAS: MVFR in Alice, Rockport, Palacios, in Bay City, in Sugar Land, in Jasper, and in Conroe. IFR in Huntsville. light rain was being reported during the last few observations at the Houston Hobby Airport. LOUISIANA: light rain in Boothville. LIFR in Port Fourchon. rain was reported in Lafayette during many of the last observations. MISSISSIPPI: light rain earlier at the Stennis International Airport. rain in Hattiesburg. ALABAMA: VFR/no ceilings. FLORIDA: MVFR in Milton. IFR in Crestview. rain and thunder in Punta Gorda. ...THE CARIBBEAN SEA... Upper level NW wind flow is moving through the Yucatan Channel into the NW Caribbean Sea. This NW wind flow moves toward the SW corner of the Caribbean Sea, and toward the coast of Colombia. A tropical wave is moving through the Mona Passage. Upper level cyclonic wind flow is moving around a trough that passes through the Mona Passage, and into the eastern part of the Caribbean Sea. 24-HOUR RAINFALL TOTALS IN INCHES FOR THE PERIOD ENDING AT 27/0000 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...1.15 in Bermuda, and 0.63 in Guadeloupe, and 0.04 in Tegucigalpa in Honduras. ...HISPANIOLA... Upper level cyclonic wind flow is moving around a trough that cuts through the eastern part of the Caribbean Sea. Upper level N wind flow is moving across Hispaniola. Earlier scattered to numerous strong convective precipitation was covering Haiti and parts of its border with the Dominican Republic. Scattered moderate to isolated strong now is off the coast of southern Haiti. SURFACE OBSERVATIONS...FOR PORT-AU-PRINCE IN HAITI: as of 27/0200 UTC: MVFR; scattered cumulonimbus clouds. rain and thunder were reported in observations during the last hour. FOR THE DOMINICAN REPUBLIC...Barahona: as of 27/0000 UTC; VFR/no ceilings; few cumulonimbus clouds. Santo Domingo/La Romana/ Punta Cana: VFR/no ceilings. Santiago: rain and thunder. Puerto Plata: VFR/no ceilings; few cumulonimbus clouds. The GFS MODEL forecast for 250 MB shows that N wind flow will move across the area during day one. The N wind flow will become cyclonic as a cyclonic circulation center/trough moves across Hispaniola during day one. More cyclonic wind flow will be present during the first half of day two. Expect S wind flow for the rest of day two. The GFS MODEL forecast for 500 MB and for 700 mb shows that SE wind flow will be moving across the area for day one, and for the first half of day two. Expect NE and E wind flow for the second half of day two. A ridge will extend from the Atlantic Ocean toward the Greater Antilles. ...THE ATLANTIC OCEAN... Upper level cyclonic wind flow is in the central sections of the Atlantic Ocean, from 30N northward between 50W and 70W. A cold front passes through 32N49W to 31N53W. A stationary front, that is dissipating along the western end of it, continues from 31N53W to 30N60W and 30N66W. Convective precipitation: widely scattered moderate to isolated strong from 26N to 31N between 49W and 57W. isolated moderate elsewhere from 20N northward between 60W and 70W. A surface ridge passes through 32N31W, 25N46W, 24N66W, toward the NW Bahamas. For additional information please visit http://www.hurricanes.gov/marine $$ MT