000 AXNT20 KNHC 131113 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 AM EDT TUE SEP 13 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 0600 UTC surface analysis and satellite imagery through 1045 UTC. ...SPECIAL FEATURES... The center of Tropical Storm Ian at 13/0900 UTC is near 24.0N 51.7W. Ian is moving north-northwestward, or 335 degrees, 8 knots. The estimated minimum central pressure is 1005 mb. The maximum sustained wind speeds are 40 knots with gusts to 50 knots. Convective precipitation: numerous strong within 100 nm to 250 nm of the center in the NE quadrant. Please read the latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT5/WTNT35 KNHC and the Forecast/Advisory under the AWIPS/WMO headers MIATCMAT5/WTNT25 KNHC for more details. ...TROPICAL WAVES... A 1010 mb low pressure center is near 12N20W. Convective precipitation: scattered strong from 11N to 13N between 19W and 21W, and from 14N to 16N between 21W and 23W. An Atlantic Ocean tropical wave is along 31W/32W, from 15N southward. Convective precipitation: embedded in the monsoon trough. A tropical wave is along 90W/91W, from 21N in the southwestern corner of the Gulf of Mexico, just to the west of the Yucatan Peninsula, southward. Convective precipitation: scattered moderate to isolated strong in northwestern Guatemala and neighboring Mexico. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through the coastal sections of Senegal near 15N17W, to the 1010 mb low pressure center that is near 12N20W, to 12N31W, to 07N38W, and to 06N45W. Convective precipitation: widely scattered moderate to isolated strong within 150 nm to 250 nm on either side of 14N17W 10N30W 04N47W. ...DISCUSSION... ...THE GULF OF MEXICO... An upper level trough is moving into the eastern half of the Gulf of Mexico. Upper level cyclonic wind flow covers the entire area. A 1011 mb low pressure center is near 24N89W. Convective precipitation: Isolated moderate from 91W eastward. ...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: KVAF, KGRY, KEIR, KSPR, KVOA, and KVKY. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA...TEXAS: rain and thunder have ended near Galveston. light rain in Pearland. MVFR in Victoria and Palacios. LOUISIANA: MVFR in Port Fourchon. MISSISSIPPI: LIFR in McComb. ALABAMA and FLORIDA: VFR/no ceilings. ...THE CARIBBEAN SEA... Broad upper level cyclonic wind flow covers the Caribbean Sea that is from 80W eastward. Much of the cyclonic wind flow has to do with the Atlantic Ocean-to-Caribbean Sea trough that is along 23N61W, across Hispaniola, to 16N73W in the Caribbean Sea, and to 12N78W. Convective precipitation: Isolated moderate in the Caribbean Sea from 15N northward between 67W and 76W. 24-HOUR RAINFALL TOTALS IN INCHES FOR THE PERIOD ENDING AT 13/0000 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...0.31 in Tegucigalpa in Honduras. The monsoon trough is along 11N between 73W in northern Colombia and 82W, beyond southeastern Nicaragua. Convective precipitation: Possible rainshowers in remnant debris clouds, that are from 13N southward from 73W westward. ...HISPANIOLA... Upper level cyclonic wind flow spans the island. An upper level trough passes through the Atlantic Ocean near 23N61W, across Hispaniola, to 16N73W in the Caribbean Sea, and to 12N78W. Convective precipitation: Isolated moderate in the Caribbean Sea from 15N northward between 67W and 76W. SURFACE OBSERVATIONS...FOR THE DOMINICAN REPUBLIC...Santo Domingo/La Romana/Punta Cana: VFR/no ceilings; few cumulonimbus clouds in Santo Domingo. Santiago/Puerto Plata: VFR/no ceilings. FOR HISPANIOLA: The GFS MODEL forecast for 250 MB shows that cyclonic wind flow and a trough will cover the area for most of the next 48 hours. SW wind flow will move across Hispaniola during the last 12 hours or so, as the trough slides westward into the Windward Passage. The GFS MODEL forecast for 500 MB shows that easterly wind flow will move across Hispaniola during the next 48 hours. The easterly wind flow is related to large- scale anticyclonic wind flow, from the Atlantic Ocean, into parts of the Caribbean Sea. The GFS MODEL forecast for 700 MB shows that NE-to-E wind flow will be moving across the area during the next 48 hours, with a large-scale Atlantic Ocean-to- Caribbean Sea ridge. ...THE ATLANTIC OCEAN... from 20N northward to the west of the 32N56W-to-Hispaniola upper level trough: Upper level NE wind flow is merging with upper level anticyclonic wind flow, in this area. Broad surface anticyclonic wind flow covers the Atlantic Ocean from 20N northward 60W and 78W. A surface trough runs from northeastern Florida, to a 1012 mb low pressure center that is along the Florida coast about 30 nm to the northeast of Lake Okeechobee, to 24N79W. Convective precipitation: scattered strong from 25N to 31N between 77W and the coast of Florida and southern Georgia. Significant development of this system is unlikely since the low is expected to move inland into the central and northern sections of the Florida peninsula through tonight. It is likely that locally heavy rainfall and gusty winds may continue in the northwestern Bahamas during the morning today, and then spread across parts of the Florida peninsula later today. An upper level trough extends from 32N56W, to an upper level cyclonic circulation center that is near 28N58W, to 23N61W, across Hispaniola, to 16N73W in the Caribbean Sea, to 12N78W. Convective precipitation: Isolated moderate from 20N northward between 57W and 74W. Isolated moderate in the Caribbean Sea from 15N northward between 67W and 76W. An upper level trough extends from a 30N14W cyclonic circulation center, across the Canary Islands, to 20N27W and 15N34W. Convective precipitation: no significant deep convective precipitation. Broad surface anticyclonic wind flow covers the Atlantic Ocean from 20N northward between Africa and 45W. A 1021 mb high pressure center is near 32N41W. For additional information please visit http://www.hurricanes.gov/marine $$ MT