000 AXNT20 KNHC 141746 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 145 PM EDT Thu Jun 14 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 1200 UTC surface analysis and satellite imagery through 1545 UTC. ...TROPICAL WAVES... A tropical wave is in the E Atlc with axis extending from 11N26W to 03N27W, moving W at 10 kt. The wave is in a favorable wind shear environment, and the CIRA LPW show moderate moisture associated with it. The GOES-16 Geocolor RGB imagery shows the presence of the Saharan Air Layer dust and dry air N of the wave at 15N. Convection directly associated with the wave has diminished. A tropical wave is in the central Atlc with axis extending from 12N42W to 03N43W, moving W at 10-15 kt. GOES SAL and Dust RGBs show the wave has dry air and dust N of 12N. Upper level diffluent flow and shallow moisture in the vicinity of the ITCZ supports widely scattered moderate convection from 04N to 11N between 35W and 42W. A tropical wave is E of the Windward Islands with axis extending from 13N57W to 03N59W, moving W at 5-10 kt. The Saharan Air Layer dust and dry air is N of 11N. This factor along with strong wind sheer in the region is hindering the development of deep convection. A tropical wave is in the central Caribbean with axis extending S from the southern coast of Cuba near 20N77W to across central Jamaica to near eastern Panama near 09N79W, moving west at 15 kt. Satellite imagery shows SAL dry air moving across the central and E Caribbean, which along with strong wind sheer is hindering the development of deep convection at the time. A tropical wave is over the SW Gulf of Mexico W of the Yucatan Peninsula with axis extending from 24N93W to across SE Mexico, moving west at 10 kt. Scattered moderate to strong convection is S of 23N W of 90W to the coast of Mexico. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 11N15W to 08N18W. The ITCZ extends from 08N18W to 06N25W, then resumes west of a tropical wave near 06N28W continuing to 06N41W, then resumes again W of another tropical wave near 06N44W and continues to the coast of South America near 05N53W. Besides the convection mentioned in the tropical waves section, scattered moderate and isolated strong convection is within 180 nm either side of the axis E of 26W to the coast of Africa. ...DISCUSSION... GULF OF MEXICO... The Atlantic subtropical ridge extends W to the NW Gulf of Mexico along 28N. Scattered showers and isolated thunderstorms extend from the Yucatan Channel northward to across the eastern Gulf of Mexico. In the upper levels, a low is centered near 25N91W with a trough axis extending NW to the Texas coast and SE to the Yucatan peninsula. The tropical wave in the SW Gulf will gradually weaken into a broad and elongated area of low pressure through Fri into early Sat, with the pressure gradient supporting fresh to strong SE flow across the western Gulf of Mexico Sat into Sun. CARIBBEAN SEA... The tropical wave in the central Caribbean will continue westward across the remainder of the basin through the early part of the weekend, while another tropical wave currently in the Tropical N Atlantic will move into the eastern Caribbean on Fri and Sat. Scattered showers and thunderstorms are S of 11N in the SW Caribbean, and in the NW Caribbean W of 85W. Otherwise, mostly fair weather is over the E Caribbean. In the upper levels, an upper level trough is over the western Caribbean along 81W. A large upper level ridge is over the remainder of the Caribbean with axis along 72W. Strong trades currently across the central Caribbean will shift slightly SW across the waters between 70W and 85W through the end of the week, then begin to diminish into the early part of the weekend as the pressure gradient weakens slightly. ATLANTIC OCEAN... Diffluent southwesterly upper level flow is over the SW N Atlantic. A weak surface trough may be present from 28N75W to 25N77W with scattered showers and thunderstorms within 120 nm SE of the trough axis. Farther E, an upper level trough in the central Atlantic supports a stalling cold front from 32N52W to 26N58W. A pre-frontal trough is dissipating as is associated convection. Otherwise, a 1030 mb high is centered over the E Atlantic near 35N31W producing surface ridging over the E Atlantic E of 50W and N of 20N. This ridge is forecast to shift E Fri and Sat while the front gradually weakens. For additional information please visit http://www.hurricanes.gov/marine $$ Lewitsky