000 AXNT20 KNHC 311755 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 155 PM 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 1200 UTC surface analysis and satellite imagery through 1745 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 of AGADIR. ...TROPICAL WAVES... A tropical wave is in the central Atlc with axis extending from 12N34W to 02N34W, moving W at 20 kt within the last 24 hours. The wave is in a region of favorable wind shear S of 09N, is in a moderate moist environment from the surface to 850 mb and is under a middle to upper level diffluent flow. All these factors support scattered moderate convection from 02N-09N between 31W-40W. A tropical wave is in the western Atlantic with axis extending from 11N45W to 03N46W, moving W at 10-15 kt within the last 24 hours. CIRA LPW imagery show a very moist low level environment. However, Saharan dry air and dust as well as unfavorable wind shear hinder deep convection at the time. A tropical wave is in the SW Caribbean with axis extending from 12N73W to inland Colombia, moving W at 20 kt within the last 24 hours. There is no convection associated with this wave in the basin. ...ITCZ/MONSOON TROUGH... The monsoon trough is inland over Africa. The ITCZ begins near 10N15W to 06N22W to 05N32W...then resumes W of a tropical wave near 06N36W and continues to 06N45W...then resumes W of a second tropical wave near 05N48W to 05N52W. Besides the convection associated with the waves, scattered moderate convection and isolated tstms are from 02N-07N between 18W-29W and from 02N-07N W of 47W. Isolated showers are from 06N-12N E of 21W. ...DISCUSSION... GULF OF MEXICO... The outer rainbands of a broad area of low pressure S of Mexico in the EPAC waters extend across the SW Gulf where a 1013 mb low has recently formed SE of the Laguna Tamiahua, Mexico near 21N96W. Middle to upper level diffluent flow embedded in a ridge enhance the convection to scattered heavy showers and isolated tstms S of 26N W of 91W. A former weak center of low pressure in the NW basin has dissipated, leaving an elongated surface trough extending along the coast of Texas near 28N96W to SE Louisiana near 30N89W to the Florida Panhandle near 30N86W. Scattered heavy showers and tstms are within 75 nm off the coasts of Mississippi, Alabama and the Florida Panhandle to 85W. Isolated showers and tstms are in the NW basin N of 26N. A weak surface ridge dominates the remainder basin, thus supporting light to moderate SE winds basin-wide. The low in the SW basin will slightly intensify during the next two days and then move northward Saturday. Return flow will prevail elsewhere. CARIBBEAN SEA... The outer rainbands of a broad area of low pressure S of Mexico over EPAC waters extend to the far NW Caribbean, thus supporting isolated showers W of 84W. Similar convection is in the SW basin associated with the monsoon trough that extends across Costa Rica and Panama to a 1009 mb low near 11N75W. A tropical wave is to the east of this low along 74W, however no convection is associated with it. See the tropical waves section for further details. A middle to upper level low N-NE of Hispaniola continue to support scattered heavy showers and tstms in the Dominican Republic, the Mona Passage and Puerto Rico as well as adjacent waters. These showers will slightly diminish through Friday evening as the upper level low supporting it shifts east. HISPANIOLA... A middle to upper level low N-NE of Hispaniola continue to support scattered heavy showers and tstms in the Dominican Republic and adjacent waters. These showers will slightly diminish through Friday evening as the upper level low supporting it shifts east. ATLANTIC OCEAN... Two tropical waves are over the tropical Atlantic. Please refer to the Tropical Waves section for more details. Showers and tstms are in Dominican Republic NE adjacent waters associated with a middle to upper level low in the same region. Otherwise, the remainder basin is under the influence of a broad surface ridge that is anchored by a 1022 mb high near 29N42W and a second high of 1023 mb near 28N67W. A cold front is entering the NE corner of the SW N Atlc waters, which will move to central Atlc waters Thu morning. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos