000 AXNT20 KNHC 301102 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 702 AM EDT Sun Jul 30 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 0600 UTC surface analysis and satellite imagery through 1030 UTC. ...TROPICAL WAVES... A tropical wave came off the W coast of Africa earlier today. Its axis extends from 18N20W to 07N20W. The wave is in a region of low to moderate vertical wind shear and is underneath upper level divergent flow. CIRA LPW imagery show abundant low level moisture associated with this wave that along with the aforementioned factors support numerous heavy showers from 08N to 13N between 19W and 27W. A tropical wave is in the central Atlantic with axis extending from 18N36W to 06N37W, moving west at 10-15 kt within the last 24 hours. The wave is in a region of low vertical wind shear, but is being severely affected by Saharan dry air and dust intrusion to its environment. This dry air and dust are affecting mainly the central and northern environment of the wave. Shallow moisture confined to the monsoon trough support scattered moderate convection from 06N to 10N between 35W and 43W. A tropical wave is in the central Atlc with axis extending from 16N46W to 06N47W, moving W at 15 kt within the last 24 hours. The wave is in a region of moderate to strong vertical wind shear, and continues to be severely affected by Saharan dry air and dust intrusion to its environment, which is limiting convection to scattered showers from 04N to 09N between 44W and 52W. A tropical wave is E of the Lesser Antilles with axis extending from 19N58W to 08N59W, moving west at 10-15 kt within the last 24 hours. The wave is in a low to moderate vertical wind shear region and continues to be affected by Saharan dry air and dust intrusion to its environment, which is inhibiting the development of deep convection. Scattered showers are from 08N to 12N between 56W and 60W. A tropical wave is in the W Caribbean with axis extending from 18N79W to 09N80W, moving W at 20 kt within the last 24 hours. The wave is associated with abundant low level moisture, particularly in the SW Caribbean where along with the EPAC monsoon trough support scattered heavy showers and tstms S of 14N W of 77W. A tropical wave is moving across W Honduras and El Salvador into EPAC waters. Its axis extends from 16N88W to 07N90W, moving W at 20-25 kt within the last 24 hours. Isolated showers are over Honduras and across El Salvador extending to the Gulf of Honduras. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from 13N16W to 10N30W to 08N46W. The ITCZ extends from 07N50W to 07N58W. For convection information see the Tropical Waves section above. ...DISCUSSION... GULF OF MEXICO... A cold front is moving along the northern Gulf being supported by a deep layered trough aloft that extends to far W Atlc waters. A pre-frontal surface trough extends from northern Florida to 29N83W to 28N90W to 27N93W. Middle level diffluent flow along with shallow moisture in the northern Gulf support scattered heavy showers and tstms N of 26N. Otherwise, variable gentle to light winds dominate over the basin. The front will continue to dip south today and is forecast to stall over central Florida this evening. Scattered heavy showers and tstms are expected over the NE and SE Gulf during this period. CARIBBEAN SEA... A tropical wave moving across Belize, Guatemala and El Salvador is generating isolated showers in the Gulf of Honduras. A second tropical wave is moving over western Caribbean waters supporting scattered heavy showers and tstms in the SW basin. See tropical waves section above for further details. Otherwise, fresh to strong winds persist in the south-central Caribbean S of 14N between 69W and 73W. A new tropical wave will be entering the E basin this evening with possible isolated showers. ...HISPANIOLA... Water vapor and CIRA LPW imagery show dry across and in the vicinity of the Island, which is supporting fair weather this morning. Except for afternoon/early evening showers due to daytime heating, fair weather is expected the next two days. ATLANTIC OCEAN... Diffluent flow aloft between a deep layer trough over the E CONUS, and a broad upper ridge anchored over Texas extending SE to the norther Bahamas support isolated showers W of 74W. Four tropical waves are moving across the basin. See the section above for details. Otherwise, a broad surface ridge anchored by a 1028 mb high near 34N41W covers the remaining basin and supports fair weather. A cold front will move into SW N Atlc waters today with showers and fresh winds. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos