000 AXNT20 KNHC 171743 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 143 PM EDT Sun Jun 17 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 1700 UTC. ...TROPICAL WAVES... Three tropical waves are noted between the W coast of Africa and the Lesser Antilles. A tropical wave axis extends from 02N22W to 12N22W. This system is moving W around 10 kt and is well defined in the TPW product as well as in model diagnostics guidance. Scattered moderate convection is present within 120 nm of the wave axis between 04N and 08N. A tropical wave over the E Atlantic has an axis extending from 02N42W to 12N39W, moving W at 5 to 10 kt. A modest surge of moistened air is noted in association with the wave in TPW imagery. Only limited cloudiness and isolated showers are associated with this wave. A tropical wave over the central Atlantic has an axis extending from 05N55W to 14N52W, moving W around 15 kt. The wave coincides with a high amplitude bulge of moisture as depicted in the TPW product. Currently, scattered moderate and isolated strong convection is seen from 08N to 11N between 52W and 55W. A tropical wave moving westward over the eastern Caribbean has an axis extending from 12N70W to 19N68W, moving W around 15 kt. African dust surrounds the wave. As a result, only shallow moisture and virtually no convection is associated with this wave. A tropical wave moving across the border of Guatemala and Mexico has an axis extending from 12N92W to 19N92W and is moving W around 15 kt. TPW satellite imagery indicates this wave is embedded in deep layer moisture. The wave is also interacting with an upper-level trough over the Gulf of Mexico. Scattered to numerous moderate and isolated strong convection is occurring from 11N to 20N between 91W and 96W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Guinea Bissau on the coast of Africa near 12N15W to 06N27W. The ITCZ continues from 06N27W to 04N34W. In addition to the convection mentioned in the Tropical Waves section, Numerous moderate and scattered strong convection is evident from 07N to 09N between 13W and 17W. Scattered moderate and isolated strong convection is found elsewhere from 04N to 10N between 11W and 18W. ...DISCUSSION... GULF OF MEXICO... An upper-level trough extends across the western Gulf from 25N88W to a low centered near 22N94W to 24N94W. Fresh to locally strong winds are occurring to the NE of the low primarily over the central Gulf waters from 25N to 29N between 86W and 92W. Scattered moderate and isolated strong convection covers much of the central Gulf from 25N to 28N between 87W and 93W. Heavy rains and gusty winds will continue to head NW across the Gulf waters today and tonight and cross the Texas and southwestern Louisiana coasts. Weak 1020 mb high pressure resides over northern Florida near 30N83W. The upper-level trough will gradually move WNW through Mon, accompanied by numerous showers and thunderstorms that could produce rough seas. The upper-level trough is inducing surface troughing along the Texas coast. A tightening of the pressure gradient between the surface trough and high pressure that extends westward from the Atlantic will continue to support fresh to strong SE winds over the west-central Gulf waters. These winds will spread westward through Tue while gradually diminishing as the trough shifts inland over Texas. CARIBBEAN SEA... Strong trades across the south central Caribbean between 69W and 76W will gradually decrease in areal coverage through mid week. The strongest winds will become confined to the S central waters, with similar pulsing winds continuing in the vicinity of the Gulf of Honduras. A tropical wave will reach the waters E of the Lesser Antilles tonight, then enter the eastern Caribbean Tue through Wed night. This system is expected to be accompanied by scattered showers and thunderstorms. As the wave passes across the Lesser Antilles into the eastern Caribbean, it will bring gusty winds and a modest increase in showers and thunderstorms to the Leeward Islands, the UK/US Virgin Islands and Puerto Rico by mid week. ATLANTIC OCEAN... A cold front extends SW from 32N57W to 26N71W to 29N76W, then continues as a weakening cold front to 31N71W. Cloudiness, scattered showers and isolated thunderstorms are present along and up to 150 nm SE of the front to the E of 70W. High pressure measuring 1032 mb centered over the Azores near 38N26W ridges SW to N of Puerto Rico near 22N67W. The cold front will stall over and east of the northern Bahamas during the next couple of days, then weaken. The high pressure ridge over the Azores will continue to ridge SW across the western Atlantic. For additional information please visit http://www.hurricanes.gov/marine $$ McElroy