000 AXNT20 KNHC 080605 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 105 AM EST Fri Dec 8 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...SPECIAL FEATURES... ...GALE-FORCE WINDS IN THE GULF OF MEXICO... A stationary front passes through central Florida near 28N82W, to 26N90W, to a 1010 mb low pressure center that is near 24N93W. The stationary front continues from the 1010 mb low pressure center, to the Isthmus of Tehuantepec of southern Mexico. Expect N-to-NE gale-force winds and sea heights ranging from 12 feet to 16 feet, within 90 nm of the line from 29N93W to 26N95W. Gale-force winds are being forecast with respect to the cold front, during the next 42 hours. Please read the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 for more details. Upper level SW wind flow spans the entire Gulf of Mexico. Upper level moisture is moving from the Yucatan Channel toward and across the southern half of Florida. Upper level moisture also is to the north of the line that runs from the coast of Mexico near 23N97W, to 25N90W, beyond 29N83W. Precipitation: rainshowers are possible/likely across the Gulf of Mexico. ...ITCZ/MONSOON TROUGH... The monsoon trough passes through the coastal sections of Guinea near 10N14W, to 07N21W. The ITCZ continues from 07N21W to 03N33W, 04N42W, and 02N48W. Precipitation: widely scattered moderate to isolated strong rainshowers within 120 nm on either side of the line from 02N at the Prime Meridian, to 04N14W to 05N26W and 05N35W. Rainshowers are possible elsewhere from 02N to 10N between 35W and 60W. A surface trough is along 42W/43W from 05N to 10N. rainshowers are possible within 60 nm on either side of the trough. ...DISCUSSION... THE GULF OF MEXICO... Please read the SPECIAL FEATURES section for information about the current cold front, that passes through NE Florida, into the west central Gulf of Mexico, to the Mexico coast near 20N98W. ...CURRENT CONDITIONS AND WEATHER, FOR THE OFFSHORE OIL PLATFORM SITES, THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N NORTHWARD AND FROM 88W WESTWARD... mostly MVFR, with some IFR, at the platform sites. CURRENT CONDITIONS AND WEATHER, FOR THE COASTAL PLAINS OF THE U.S.A., FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... CONDITIONS WITH THE CURRENT GULF OF MEXICO COLD FRONT: MVFR/IFR and light rain in most places. some stations are reporting light snow from Victoria northward, to Jasper, and even to the greater Houston metropolitan area and surrounding smaller communities. LOUISIANA: MVFR and light rain. MISSISSIPPI: MVFR/IFR and a mixture of light rain and light snow, and some VFR. ALABAMA: some MVFR/VFR. other areas of LIFR/IFR and heavy rain. FLORIDA: IFR and heavy rain from Cross City toward the NW and W. MVFR/IFR, and a small bit of LIFR, from Brooksville to Sarasota. LIFR and fog from Punta Gorda to the Fort Myers metropolitan area. THE CARIBBEAN SEA... An upper level ridge extends from N Colombia to the NW part of Cuba. A surface trough is along 14N80W 19N85W, in the area of the offshore waters of Honduras and Nicaragua. Precipitation: scattered strong rainshowers from 13N to 17N between 80W and 83W. isolated moderate elsewhere from 13N northward from 80W westward. The monsoon trough is along 10N75W 10N80W, beyond southern Nicaragua. Precipitation: isolated moderate to locally strong rainshowers from 14N southward from 76W westward. Isolated moderate rainshowers cover the Caribbean Sea from the Greater Antilles southward to 13N from 72W eastward. This precipitation is related to remnant atmospheric instability, from an already- dissipated frontal boundary of the last few days, that has moved into the area from the Atlantic Ocean. ...HISPANIOLA... Upper level NW wind flow is moving across the area. Broad upper level anticyclonic wind flow spans the Caribbean Sea. SURFACE OBSERVATIONS...HAITI: VFR. scattered cumulonimbus clouds in Port-au-Prince. in the DOMINICAN REPUBLIC: VFR at all the observation stations. The GFS MODEL forecast for 250 mb shows that a ridge will start along the line from N Colombia to SE Cuba, and then to a line from N Colombia across Hispaniola. Expect W-to-NW wind flow during the next 48 hours. The GFS MODEL forecast for 500 mb shows that E-to-SE wind flow will move across the area during the next 2 days, with an Atlantic Ocean ridge. The GFS MODEL forecast for 700 mb shows that broad E-to-SE wind flow, with an intermittent inverted troughs during day one, and broad anticyclonic wind flow at the end of day two. THE ATLANTIC OCEAN... A deep layer trough is in the east-central sections of the Atlantic Ocean, along 32N37W 27N36W 20N35W. A trough/shear line continues from 20N35W to 16N42W 14N52W 15N60W. The trough supports a cold front that curves through 32N32W to 25N35W to 20N40W. A stationary front continues from 20N40W to 17N47W, and to 16N54W. A surface trough continues from 16N54W to 16N65W in the Caribbean Sea. A large area of comparatively drier air in subsidence is to NW of the trough/shear line. Precipitation: scattered moderate to strong from 22N northward between 31W and 33W. Surface anticyclonic wind flow covers the Atlantic Ocean from 17N northward between 42W and 75W. A 1023 mb high pressure center is near 30N60W. A surface ridge passes through the Madeira Archipelago, to 25N23W to 17N28W, and 08N34W. 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