000 AXNT20 KNHC 032339 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 739 PM EDT Tue Oct 3 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...SPECIAL FEATURES... A tropical wave over the SW Caribbean extends from 20N81W to 08N81W moving W at 10 kt. A 1008 mb low is embedded on the wave axis near 11.5N81W. Clusters of scattered moderate to isolated strong convection are from 08N-16N between 76W-86W. Environmental conditions are forecast to steadily become more conducive for development, and this system is expected to become a tropical depression within the next few days. The large disturbance should move slowly northwestward to northward across or near the eastern portions of Nicaragua and Honduras, move into the northwestern Caribbean Sea on Thursday or Friday, and emerge over the southern Gulf of Mexico by the weekend. Interests in Nicaragua and Honduras should monitor the progress of this system over the next couple of days. Regardless of development, this system will likely produce heavy rains over portions of Central America during the next few days. There is a medium chance of tropical cyclone formation within the next 48 hours. ...TROPICAL WAVES... A tropical wave extends from 17N34W to 08N37W moving W at 15-20 kt. The wave remains low amplitude and coincides with modest troughing at 700 mb. Satellite TPW imagery indicates this wave is embedded in an area of deep-layer moisture. Scattered moderate to isolated strong convection is from 07N-11N between 37W-44W. Scattered showers are elsewhere within 180 nm of the wave axis. A tropical wave over the E Caribbean extends from 23N60W to 09N59W moving W at 10-15 kt. The wave coincides with broad 700 mb troughing and continues to interact with an upper-level low centered near 16N61W. Divergent upper-level winds on the east side of the upper low are supporting widely scattered moderate convection over the Atlantic from 10N-22N between 51W-61W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 09N13W to 09N22W. The Intertropical Convergence Zone axis extends from 09N22W to 09N30W to 07N43W to 09N53W. Besides the convection associated with the tropical waves, scattered moderate to isolated strong convection is along the coast of W Africa from 06N-13N between 08W-15W. ...DISCUSSION... GULF OF MEXICO... Surface ridging is over the northern Gulf of Mexico with 20-25 easterly winds. The surface pressure gradient is fairly tight and 30 kt winds may occur over the NE Gulf over the next 24 hours. A surface trough is over the SW Gulf of Mexico from 24N99W to 17N94W. Scattered moderate convection is within 90 nm of this trough. In the upper levels, a small upper level high is centered over the S Texas near 28N96W. A good amount of upper level moisture is along the Texas and Mexico coasts. Expect over the next 24 hours for convection with wind gusts to advect over S Florida. Also expect the surface trough to persist over the Bay of Campeche with convection. Furthermore, expect the surface ridging to persist over the northern and central Gulf of Mexico. CARIBBEAN SEA... A tropical wave with an embedded low is over the SW Caribbean that merits watching. Another tropical wave is over the E Caribbean. See above. In addition, the eastern extent of the E Pacific monsoon trough extends from S Guatemala to N Costa Rica to N Colombia. Scattered moderate to isolated strong convection is over all of Central America S of 20N. Otherwise, 10-20 kt tradewinds are over the Caribbean. ...HISPANIOLA... Currently skies remain mostly fair across the island. Some showers are over the southern and southwestern coastal waters, moving south. Hispaniola is presently in between tropical waves. ATLANTIC OCEAN... A surface trough extends from the N Bahamas near 26N78W to central Cuba near 21N80W. Scattered moderate to strong convection is within 240 nm E of the trough axis. Reports from land stations and from nearby ships, indicate that wind gusts of 40 kt have been occurring in some of the heavier convection. Although significant development of this system is not expected due to strong upper- level winds, brief squalls will likely produce locally heavy rainfall and strong gusty winds over portions of the Bahamas and the southern Florida peninsula during the next couple of days. Elsewhere, the tail end of a cold front is over the central Atlantic from 31N49W to 26N64W. A stationary front continues to 26N74W. Widely scattered moderate convection is within 120 nm of the fronts. Broad surface ridging extends SW from a 1027 mb surface high centered over the Azores near 40N26W. The ridging dominates the Atlantic N of 22N and E of 45W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa