000 AXNT20 KNHC 171801 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 201 PM EDT Mon Jul 17 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 1715 UTC. ...SPECIAL FEATURES... A 1010 mb low pressure center is near 11N51W. Convective precipitation: Scattered moderate to isolated strong from 10N to 12N between 51W and 53W. Environmental conditions are conducive for some development before the system reaches the Lesser Antilles late Tuesday or early Wednesday. Less favorable upper-level winds are expected to hinder additional development after that time. It is expected that this system may bring locally heavy rainfall and gusty winds to parts of the Lesser Antilles beginning on Tuesday. An Air Force Reserve reconnaissance aircraft is en route in order to investigate the situation. The chance for formation into a tropical cyclone during the next 48 hours is medium. Please refer to the latest Tropical Weather Outlook...MIATWOAT/ABNT20 KNHC... for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 33W/34W from 20N southward. Convective precipitation: widely scattered moderate to isolated strong from 10N to 14N between 30W and 36W. An Atlantic Ocean tropical wave is along 55W/56W from 19N southward. Convective precipitation: isolated moderate from 12N to 24N between 54W and 60W. A Caribbean Sea tropical wave is along 82W/83W from 23N in NW Cuba, southward. Convective precipitation: widely scattered to scattered moderate and isolated strong from 17N southward between 80W and 86W, including interior sections and coastal waters of Nicaragua and Honduras. A SW Gulf of Mexico tropical wave is along 95W/96W from 22N southward. The wave is moving through southern Mexico, just to the west of the Isthmus of Tehuantepec of southern Mexico. Convective precipitation: Weakening precipitation and convective debris clouds are present from 24N southward between 90W and 96W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through coastal sections of Senegal near 14N17W to 14N24W, 09N37W, and 10N51W. Convective precipitation: scattered to numerous strong is in the coastal plains and coastal waters of Africa from 10N to 14N between 14W and 17W. Isolated moderate to locally strong from 08N to 10N between 12W and 14W in the coastal plains. Widely scattered moderate to isolated strong from 04N to 11N between 35W and 45W. Scattered moderate to strong from the Equator to 02S between 35W and 40W. ...DISCUSSION... ...THE GULF OF MEXICO... An upper level cyclonic circulation center is moving inland along the coast of Mexico near 21N97W. Cyclonic wind flow covers Mexico and the Gulf of Mexico from 17N to 25N between 89W and 106W. A weakening cyclonic circulation center is near 23N86W. Weakening precipitation and convective debris clouds are present from 24N southward between 90W and 96W. The surface pressure pattern is weak, with little gradient. Convective precipitation: rainshowers and thunder are in the coastal waters, and reaching land in some cases, from 27N northward between 83W for Florida and 95W for the upper Texas Gulf coast. rainshowers and thunder also are present in along the SW coast of Florida from 25N to 27N between 81W and 83W, and in the coastal plains of Texas from 27N to 28N between the coast and 98W. ...THE CARIBBEAN SEA... Broad upper level anticyclonic wind flow covers the area that is from 18N southward, from the Yucatan Peninsula of Mexico and Guatemala eastward to 70W, and southeastward. Broad and weak cyclonic wind flow, and comparatively drier air in subsidence that is evident in water vapor imagery, cover the Caribbean Sea from 70W eastward. Weak upper level cyclonic wind flow also covers the rest of the area, in the NW corner of the Caribbean Sea. The monsoon trough is along 09N/10N between 74W/75W in Colombia, beyond NW Costa Rica, into the eastern Pacific Ocean. Convective precipitation: isolated moderate from 12N southward between 75W and 80W. 24-hour rainfall totals in inches, for the period that ended at 17/1200 UTC, according to the PAN AMERICAN TEMPERATURE AND PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...are: 1.45 in Merida in Mexico, 0.17 in Guadeloupe, 0.10 in Bermuda, 0.07 in San Juan in Puerto Rico and in St. Thomas in the Virgin Islands, 0.03 in Nassau in the Bahamas. a TRACE was reported in Freeport in the Bahamas, in Montego Bay in Jamaica, and in Trinidad. ...HISPANIOLA... An upper level trough is in the Atlantic Ocean, to the north of Hispaniola, between 62W and 75W. Upper level anticyclonic wind flow, westerly at the moment, is in the Caribbean Sea to the south of Hispaniola. A surface ridge passes through the Atlantic Ocean near 28N61W, to 22N71W, to Hispaniola. SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: VFR. for the DOMINICAN REPUBLIC: Barahona: VFR. Santo Domingo: earlier rain has ended for the moment. few towering cumulus clouds. La Romana: VFR. Punta Cana: VFR. Santiago: MVFR. ceiling 2200 feet. few cumulonimbus clouds. Puerto Plata: VFR. The GFS MODEL forecast for 250 mb shows that broad cyclonic wind flow will be spanning the area during the next 48 hours. The GFS MODEL forecast for 500 mb shows that E-to-SE wind flow will be moving across the area during the next 48 hours. It is possible that even NE wind flow may be present at the end of the 48-hour forecast period. The GFS MODEL forecast for 700 mb shows that at least one inverted trough, and possibly a second one, will be moving across Hispaniola, during the next 48 hours. Expect cyclonic wind flow. ...THE ATLANTIC OCEAN... An upper level cyclonic circulation center is near 30N70W. Upper level cyclonic wind flow covers the area from 20N between 62W and 75W. Convective precipitation: widely scattered moderate to isolated strong within 90 nm on either side of the line that passes through 32N64W, to 29N67W and 23N70W. isolated moderate to locally strong covers parts of the NW Bahamas from 24N northward between 77W and 80W. An upper level cyclonic circulation center is 32N50W. Upper level cyclonic wind flow covers the area from 23N northward between 40W and 57W. Convective precipitation: isolated moderate from 31N northward between 44W and 60W. Surface anticyclonic wind flow spans the area from 20N northward between Africa and 80W. A 1031 mb high pressure center is near 34N43W. For additional information please visit http://www.hurricanes.gov/marine $$ MT