000 AXNT20 KNHC 310603 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 202 AM EDT Wed May 31 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... Please refer to the METEO-FRANCE High Seas Forecast, that is listed under the following links: MARINE...BULLETINS EXPERTISES...GRAND LARGE...METAREA II...or on the website: WWW.METEOFRANCE.COM/PREVISIONS-METEO-MARINE/BULLETIN/ GRANDLARGE/METAREA2. Gale-force winds are forecast for the area that is called: AGADIR. The OUTLOOK, for the 24 hours that follow the forecast that is valid until 01/0000 UTC, consists of: north near gale or at times gale, in AGADIR. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 30W/32W from 13N southward, moving westward 15 knots. Convective precipitation: widely scattered moderate to isolated strong in the ITCZ. An Atlantic Ocean tropical wave is along 42W/44W from 12N southward, moving westward 10 to 15 knots. Convective precipitation: widely scattered moderate to isolated strong from 06N to 08N between 40W and 44W. A Caribbean Sea tropical wave is along 67W/69W, from 13N southward, moving westward 15 to 20 knots. The wave is moving into the area of an upper level trough. Convective precipitation: no significant deep convective precipitation. A Caribbean Sea tropical wave is along 78W/79W, from 16N southward, moving westward 15 knots. Convective precipitation: no significant deep convective precipitation that just is related to the tropical wave. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through coastal sections of Senegal near 14N17W, to 10N19W 07N22W and 07N27W. The ITCZ is along 07N33W to 06N37W and 06N46W and northern sections of Suriname near 05N56W. Convective precipitation: widely scattered moderate to isolated strong from 02N to 10N between 10W and 20W, and from 02N to 08N between 20W and 36W. Isolated moderate elsewhere from 10N southward from 60W eastward. ...DISCUSSION... ...THE GULF OF MEXICO... An upper level ridge is along 88W/89W. passes through the Florida Big Bend to the Yucatan Peninsula. A stationary front is in Texas, from East Texas, into south central Texas, beyond the Texas Big Bend. A surface trough extends from a 1014 mb low pressure center that is near 28N94W, to the coast of Louisiana near 30N92W. A second surface trough is in the Gulf of Mexico, from 25N96W to 18N93W at the coast of Mexico/the northern part of the Isthmus of Tehuantepec, of southern Mexico. Convective precipitation: rainshowers are possible across the open waters of the Gulf of Mexico. The precipitation is weakening, comparatively speaking, from 90W eastward. A surface ridge passes through the NW Bahamas, toward the coastal plains of Mississippi and Alabama. ...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... LIFR: none. IFR: KATP. MVFR: KGRY, KVKY, and KMIS. CURRENT CONDITIONS AND WEATHER, FOR THE COASTAL PLAINS OF THE U.S.A., FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... Texas: MVFR in Weslaco. ALABAMA: light rain in parts of the Mobile metropolitan area. Rain has stopped for the moment in Gulf Shores. FLORIDA: light rain in the Pensacola metropolitan area. ...THE CARIBBEAN SEA... An upper level trough extends from a 22N69W cyclonic circulation center, across Hispaniola, to the Peninsula de la Guajira of NE Colombia/NW Venezuela. 16N68W in the Caribbean Sea. A surface trough is along 22N65W 19N67W 18N68W, from the Atlantic Ocean into the Mona Passage. Convective precipitation: isolated moderate from 23N in the Atlantic Ocean into the coastal plains of South America between 60W and 73W. Scattered moderate to strong is inland in Colombia and in Venezuela from 08N to 09N between Lake Maracaibo in NW Venezuela and 75W in Colombia. Convective precipitation: widely scattered moderate to isolated strong from 13N to 17N between 82W and 86W, from the coastal waters of Nicaragua to the coastal waters of Honduras. Upper level NW wind flow is on top of this area. 24-hour rainfall totals that are listed for the period that ended at 31/0000 UTC...according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are 0.03 in Guadeloupe. ...HISPANIOLA... Upper level cyclonic wind flow is moving across the area, with the current upper level trough. SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: MVFR. scattered cumulonimbus clouds. for the DOMINICAN REPUBLIC: Barahona: MVFR. ceiling 1800 feet. few cumulonimbus clouds. Santo Domingo and La Romana: VFR. few cumulonimbus clouds. Punta Cana: VFR. Santiago: few cumulonimbus clouds. Puerto Plata: VFR. The GFS MODEL forecast for 250 mb shows that cyclonic wind flow will span Hispaniola during the first 6 to 12 hours of the 48-hour forecast period, with the current trough. Expect NW wind flow, and then N wind flow, during the rest of the time. The GFS MODEL forecast for 500 mb shows that cyclonic wind flow will cover the easternmost part of the Dominican Republic during the first 6 hours or so. A cyclonic circulation center will be on top of that area. The cyclonic circulation center is forecast to move eastward a bit, and also to meander and stay near the Mona Passage, and even return to the easternmost part of the Dominican Republic. Cyclonic wind flow will cover the easternmost part of the Dominican Republic, while the cyclonic circulation center is being located in that area. Expect NE wind flow if the cyclonic circulation center is closer to Puerto Rico. The GFS MODEL forecast for 700 mb shows that easterly wind flow will move across the area during the next 48 hours. It is possible that the direction may be from the SE or the NE at times, during the overall forecast period. ...THE ATLANTIC OCEAN... An upper level trough is along 28N24W, to 22N32W, 15N39W, and to 13N44W. No significant deep convective precipitation is apparent. An upper level trough passes 32N41W to 27N47W, 25N54W, toward the 22N69W cyclonic circulation center. A cold front passes through 32N60W, to just to the south of Bermuda, to 32N69W. No significant deep convective precipitation is apparent. A surface ridge extends from a 1026 mb high pressure center that is near 33N27W, through a 1023 mb high pressure center that is near 30N42W, to a 1022 mb high pressure center that is near 26N67W, and beyond the NW Bahamas, toward coastal sections of Mississippi and Alabama. For additional information please visit http://www.hurricanes.gov/marine $$ MT ...SPECIAL FEATURES... Please refer to the METEO-FRANCE High Seas Forecast, listed under the following links: MARINE...BULLETINS EXPERTISES...GRAND LARGE...METAREA II...or on the website: WWW.METEOFRANCE.COM /PREVISIONS-METEO-MARINE/BULLETIN/GRANDLARGE/METAREA2. Gale-force winds are forecast for the area of AGADIR. The outlook for the 24 hours that follow the forecast valid until 31/1200 UTC continues to depict north near-gale to gale winds at times. ...TROPICAL WAVES... A tropical wave is in the eastern Atlantic with axis extending from 13N29W to 04N30W, moving west at 10-15 kt. Saharan dry air and dust are observed in the wave's environment, which inhibits deep convection at the time. Shallow moisture supports isolated showers along the wave's axis south of 05N. A tropical wave is in the central Atlantic with axis extending from 12N41W to 01N43W, moving west at 10-15 kt. TPW imagery shows a moderate moist environment east of the wave's axis that along with upper-level diffluence supports isolated showers south of 08N between 40W-42W. Saharan dry air is west of the wave axis inhibiting convection. A tropical wave is in the southeast Caribbean with axis extending from 13N65W to inland Venezuela near 01N66W, moving west at 10-15 kt. TPW imagery shows a moderate moist environment within this wave. Scattered moderate convection prevails within the portion of the wave that prevails over land. A tropical wave is in the southwest Caribbean with axis extending from 16N77W to the EPAC near 04N77W, moving west at 10-15 kt. Isolated moderate convection is present in the wave's environment south of 11N between 74W-79W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from 18N16W to 08N27W. The ITCZ begins near 07N33W to 07N40W, then resumes west of a tropical wave near 07N45W to 06N57W. Besides the convection associated with the waves, scattered moderate convection is within 300 nm south of the monsoon trough and east of 26W. ...DISCUSSION... GULF OF MEXICO... A 1015 mb surface low pressure is centered near 28N95W and dominates the western half of the Gulf. a surface trough extends from the low to 29N89W. A diffluent flow aloft supports scattered moderate convection between 87W-91W. To the east, a 1021 mb surface high is centered near 30N85W. In the southwest portion of the basin, the latest scatterometer data shows a surface trough extending from 25N95W to the Bay of Campeche near 20N96W. Gentle to moderate easterly winds prevail across the basin. The low and trough are forecast to dissipate by Wed morning, leaving return flow across the basin through Thu. CARIBBEAN SEA... Two tropical waves are moving across the southern portion of the basin. Please refer to the section above for details. The proximity of the monsoon trough that extends along 10N and the tropical wave. The remainder of the basin enjoys fair weather being influenced by an upper- level ridge that promotes dry air subsidence from aloft. There is an upper- level low north of Hispaniola and Puerto Rico that is keeping a diffluent flow across the islands. With this, scattered showers and thunderstorms are noted across central Hispaniola and the western half of Puerto Rico, as well as the Mona Passage. A similar weather pattern will prevail through the next 24 hours. HISPANIOLA... An upper-level low north of Hispaniola and westerly flow south of the island support diffluence aloft, which supports scattered showers and thunderstorms across the island. This shower activity is forecast to continue through Wednesday evening. ATLANTIC OCEAN... Two tropical waves are over the tropical Atlantic. Please refer to the Tropical Waves section for more details. The remainder basin is under the influence of a broad surface ridge that is anchored by a 1025 mb high south of the Azores Islands near 33N27W and a 1023 mb one near 28N43W. A cold front is forecast to enter the northeast corner of the west Atlantic by Wednesday morning then will move to central Atlantic by Thursday morning. For additional information please visit http://www.hurricanes.gov/marine $$ MT