000 AXNT20 KNHC 011808 AAA TWDAT Tropical Weather Discussion...AMENDED NWS National Hurricane Center Miami FL 205 PM EDT THU SEP 01 2016 AMENDED IN ORDER TO UPDATE INFORMATION ABOUT T.S. HERMINE 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. ...SPECIAL FEATURES... The center of Hurricane Gaston at 01/1800 UTC is near 38.0N 39.2W, or about 500 nm to the west of Faiala Island in the central part of the Azores, and about 570 nm to the west of Lajes Air Base in the Azores. Gaston is moving east- northeastward, 70 degrees, 21 knots. The estimated minimum central pressure is 980 mb. The maximum sustained wind speeds are 75 knots with gusts to 90 knots. Convective precipitation: Scattered strong from 38N to 40N between 37W and 41W. Please read the latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT2/WTNT32 KNHC and the Forecast/Advisory under the AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. The center of Tropical Storm Hermine at 01/1800 UTC is in the Gulf of Mexico, near 27.8N 85.6W, or about 120 nm to the south- southwest of Apalachicola Florida and about 165 nm to the west of Tampa Florida The tropical storm is moving north- northeastward, or 30 degrees, 12 knots. The estimated minimum central pressure is 989 mb. The maximum sustained wind speeds are 55 knots with gusts to 65 knots. Convective precipitation: Scattered strong from 23N northward into southern sections of Georgia and the southeastern corner of Alabama between northeastern Florida and 88W in the Gulf of Mexico. Surface cyclonic wind flow that is moving around Hermine covers the Gulf of Mexico from 23N northward from 91W eastward. Please read the latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC and the Forecast/Advisory under the AWIPS/WMO headers MIATCMAT4/WTNT24 KNHC for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 36W/37W, from 21N southward, moving westward 15 to 20 knots. Upper level cyclonic wind flow accompanies an inverted trough that is near the tropical wave, between 30W and 43W. Convective precipitation: isolated moderate from 11N to 18N between 32W and 47W. A surface trough is along 23N55W to 20N56W to 16N57W. Convective precipitation: isolated moderate from 13N in the Caribbean Sea to 28N in the Atlantic Ocean between 52W and 70W. The surface trough is moving under the upper level ridge. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through the coastal areas of Mauritania near 17N16W to 10N28W. The ITCZ is along 07N39W to 06N43W 09N56W, toward Trinidad. Convective precipitation: Widely scattered moderate to isolated strong from 05N to 17N between 13W and 30W. Isolated moderate from 05N to 10N between 30W and 50W. Widely scattered moderate to isolated strong from 05N to 12N between 50W and 57W. Scattered strong from 09N to 14N between 57W and 58W. ...DISCUSSION... ...THE GULF OF MEXICO... The main feature is Tropical Storm Hermine. An upper level trough covers the Gulf of Mexico from 90W westward. Convective precipitation: Scattered moderate to isolated strong from 21N to 23N between 95W and the coast of Mexico. ...FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N NORTHWARD AND FROM 88W WESTWARD... LIFR: KVOA. IFR: none. MVFR: KMDJ and KMIS. LOW LEVEL CLOUD CEILINGS AND WEATHER...FOR THE COASTAL PLAINS OF THE U.S.A. FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... TEXAS: VFR/no ceilings. LOUISIANA: VFR/no ceilings. Mississippi: VFR/no ceilings. Alabama: MVFR at the Mobile Downtown Airport. Florida: light rain and MVFR in the Pensacola metropolitan area. light drizzle and MVFR in the Panama City metropolitan area. heavy rain in Apalachicola. light rain in Tallahassee, in Perry, and in Cross City. rainshowers and thunder in Brooksville. rain and MVFR in the Tampa metropolitan area, and in Sarasota, and in Naples. ...THE CARIBBEAN SEA... Upper level cyclonic wind flow covers Hispaniola, with an upper level cyclonic circulation center on top of Haiti. A trough extends from 25N73W in the Atlantic Ocean, to Haiti, to 13N74W in the Caribbean Sea. Convective precipitation: isolated moderate from 15N to 18N between 70W and 77W. Some of the precipitation that is occurring between 60W and 70W also is moving westward into the same area that is between 70W and 77W. Upper level anticyclonic wind flow covers that part of the Caribbean Sea that is to the west and northwest of the Hispaniola cyclonic circulation center and trough. Comparatively drier air in subsidence is apparent in water vapor imagery to the east of 70W. 24-HOUR RAINFALL TOTALS IN INCHES FOR THE PERIOD ENDING AT 01/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...0.19 in Merida in Mexico, 0.15 in Trinidad, 0.06 in Monterrey in Mexico, 0.01 in Guadeloupe and in Curacao. An inverted trough is in the southwestern corner of the area. Upper level cyclonic wind flow covers the area that is from 13N southward between northern Colombia and Nicaragua and Costa Rica. The monsoon trough is along 10N72W near Lake Maracaibo in northwestern Venezuela, beyond the border of Nicaragua and Costa Rica. Convective precipitation: Isolated moderate from 12N southward. ...HISPANIOLA... Upper level cyclonic wind flow covers Hispaniola, with an upper level cyclonic circulation center on top of Haiti. A trough extends from 25N73W in the Atlantic Ocean, to Haiti, to 13N74W in the Caribbean Sea. SURFACE OBSERVATIONS...FOR PORT-AU-PRINCE IN HAITI: VFR/no ceilings. FOR THE DOMINICAN REPUBLIC...Barahona: VFR/no ceilings, and few cumulonimbus clouds. Santo Domingo/La Romana/Punta Cana: VFR/NO CEILINGS. Santiago and Puerto Plata: VFR/NO CEILINGS. FOR HISPANIOLA: The GFS MODEL forecast for 250 MB shows that day one will consist of cyclonic wind flow with the trough, becoming SE wind flow at the end of the day as the trough moves westward. Anticyclonic wind flow will cover the area, gradually, during day two, with a ridge that extends from the Atlantic Ocean, across Hispaniola, southward into the Caribbean Sea. The GFS MODEL forecast for 500 MB shows that day one will consist of E to SE wind flow. Day two will consist of NE to E wind flow. The GFS MODEL forecast for 700 MB shows that SE wind flow move across the area for the next 48 hours. ...THE REST OF THE ATLANTIC OCEAN... A 1008 mb low pressure center is near 33N76W. A surface trough extends from the low center to 31N79W. Convective precipitation: Scattered moderate to strong from 29N to 34N between 71W and 75W. Isolated moderate elsewhere from 28N northward from 68W westward. An upper level trough extends from 25N73W in the Atlantic Ocean, to Haiti, to 13N74W in the Caribbean Sea. An upper level ridge extends from a 28N61W, into the east central Caribbean Sea. An upper level trough extends from 38N04W in Spain, to 31N13W, across the Canary Islands, to 25N17W. An upper level cyclonic circulation center is near 31N28W. Cyclonic wind flow that is moving around the center covers the area from 26N to 33N between 24W and 34W. A surface ridge extends from a 1029 mb high pressure center that is near 36N27W, through 32N34W and 28N47W, to 25N67W, across the Bahamas, into the Straits of Florida. For additional information please visit http://www.hurricanes.gov/marine $$ MT