000 AXNT20 KNHC 091202 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 802 AM EDT Mon Apr 9 2018 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 0600 UTC surface analysis and satellite imagery through 1100 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Guinea-Bissau on the coast of west Africa near 11N15W to 05N16W to 02N19W. The ITCZ continues from 02N19W to 03S33W to the coast of Brazil near 03S44W. Scattered moderate and isolated strong convection is present from 02N to 06N between 13W and 16W and within an area bounded by 03N22W to 00N21W to 09S33W to 04S38W to 01N38W to 03N22W. ...DISCUSSION... GULF OF MEXICO... A quasi-stationary front extends from Tampa Florida near 28N83W to just S of Mobile Alabama near 29N88W to to 24N94W to SE of Veracruz Mexico near 19N95W. The front has begun to weaken and currently possesses not associated deep convection. Gentle to locally moderate winds generally prevail across the basin. The front will continue to weaken and retrograde N as a warm front today. A secondary push of cold air along with a developing low pressure along the frontal boundary will cause the front to transition to a cold front and push back to the SE across the Gulf Tue and Tue night. The front is forecast to exit the SE Gulf by Wed night and dissipate near the Straits of Florida by Thu. CARIBBEAN SEA... Gentle to moderate trade winds prevail over the basin. A relatively dry weather pattern is currently in place and mid to upper-level ridging extends northwestward over the basin from South America with strong subsidence noted over the eastern Caribbean. Low pres systems moving E from the United states mainland over the western Atlc continue to weaken the ridge to the N of the Caribbean. As a result, trade-wind flow over the basin remains lighter than normal. Consequently, seas are running fairly low across the area. The highest seas of around 5-8 ft are occurring near the coast of Colombia where low pres over S America tightens the pres gradient. Only subtle changes in the weather pattern are expected during the next couple of days as the surface ridge to the north remains relatively weak. Seas will briefly build to around 10 ft near the coast of Colombia early on Tue as the ridge to the N builds slightly and low pres over S America deepens. The weaker pres gradient will become reestablished Wed and Thu. ATLANTIC OCEAN... A cold front crosses the W Atlantic from 32N63W to 27N72W, then continues as a stationary boundary to Cape Canaveral Florida near 28.5N81W. Scattered showers and isolated thunderstorms are found along and up to 150 nm of the front N of 27N. Elsewhere, a large 1035 mb high located over the northeast Atlantic near 36N30W dominates the remainder of the area. Fair weather along with moderate to fresh trade winds will prevail over the tropical Atlantic north of the ITCZ and west of 30W. The western portion of the W Atlantic front is forecast to lift back to the N as a warm front today and ling up with a developing low pressure system just off South Carolina. The low will move E-NE Tue and drag a cold front across Florida. The cold front will then extend from 31N72W to South Florida by Wed morning, and dissipate across the Straits of Florida by Thu. Both fronts will be preceded by fresh to strong SW winds and building seas. For additional information please visit http://www.hurricanes.gov/marine $$ McElroy