000 AXNT20 KNHC 311736 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 136 PM EDT Thu Aug 31 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 1200 UTC surface analysis and satellite imagery through 1730 UTC. ...SPECIAL FEATURES... The now Hurricane Irma is centered near 16.9N 33.8W at 31/1500 UTC or about 565 nm west of the Cabo Verde Islands, moving west- northwest at 9 kt. Estimated minimum central pressure is 979 mb. Maximum sustained wind speed is 85 kt with gusts to 105 kt. Scattered to numerous moderate convection is observed from 14N- 21N between 30W-40W. See the latest Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT1/WTNT31 KNHC and the full Forecast/Advisory under AWIPS/WMO headers MIATCMAT1/WTNT21 KNHC for more details. ...TROPICAL WAVES... A tropical wave is over the central Atlantic with axis that extends from 23N51W to 10N51W, moving west at 10 to 15 kt. The wave coincides with an amplified 700 mb trough in initial model wind fields. TPW satellite imagery shows an area of modest deep layer moisture near the wave axis. Satellite imagery also shows an area of Saharan dust in the wave's environment. No significant convection is observed at this time. A tropical wave over the central-west Caribbean with axis from 22N78W to 09N79W, moving west at 15 to 20 kt. The wave coincides with a 700 mb troughing in initial model wind fields and curvature of low-level winds in scatterometer data. SSMI TPW imagery shows this wave is embedded in an area of modest deep layer moisture. Scattered moderate convection is over E Cuba and Haiti. Scattered showers are noted west of the wave's axis affecting the west Cuba, Central America, Yucatan Peninsula, and adjacent waters. A tropical wave over the Bay of Campeche and southeast Mexico with axis extending from 21N93W to 12N94W, moving west around 10-15 kt. The wave coincides with subtle 700 mb troughing in initial model wind fields. TPW satellite imagery shows this wave is embedded in an area of modest deep layer moisture. Scattered moderate convection is found over southeast Mexico and the Bay of Campeche south of 25N between 90W-96W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from 17N16W to 15N28W then resumes from 14N37W to 11N50W. The ITCZ is from 10N53W to 10N61W. Scattered moderate convection prevails south of the monsoon trough mainly east of 22W. Another area of scattered showers and thunderstorms are noted within 100 nm south of the other part of the monsoon trough between 36W-50W. ...DISCUSSION... GULF OF MEXICO... Tropical Depression Harvey continues to be centered over northern Louisiana while weakening. Some residual showers and thunderstorms linger between the Florida Panhandle and the western Yucatan Peninsula in a convergent southwest flow within 60 nm either side of a line from 31N87W to 22N92W. An area of scattered showers and isolated thunderstorms as the northern portion of a tropical wave moves through this area. Refer to the section above for details. Scatterometer data depicts gentle to moderate southeasterly flow across the basin, with highest speeds prevailing over the northeast waters north of 25N and east of 90W. A similar weather pattern is expected through the next 24 hours. CARIBBEAN SEA... A tropical wave is crossing the central-west Caribbean waters. See the Tropical Waves section above for additional details. The eastern portion of the E Pacific monsoon trough passes over the southwest Caribbean near 10N with isolated showers along it. An upper-level low is centered over the Caribbean north of Colombia near 14N75W. Divergent upper-level winds east of the low are triggering isolated thunderstorms over the eastern Caribbean between 64W and 75W. Satellite-derived wind data depicts moderate to fresh trades covering the basin. ...HISPANIOLA... Isolated showers are moving south of the island. Expect a dry weather pattern to prevail across the island during the next couple of days. ATLANTIC OCEAN... Hurricane Irma is over the eastern Atlantic, while a tropical wave is moving over the central Atlantic. Refer to the appropriate sections above for details about these features. A frontal boundary extends across the west Atlantic, analyzed as a cold front from 31N59W to 29N70W then as a stationary front from that point to 30N81W. Scattered showers and thunderstorms are observed along the cold front. A stationary 1019 mb surface high is centered near 25N62W. To the northeast, a pair of surface troughs extend from 32N50W to 27N54W and from 27N46W to 24N48W. Isolated showers are noted along these troughs. The remainder of the basin is dominated by a 1028 mb high centered over the Azores near 38N27W. For additional information please visit http://www.hurricanes.gov/marine $$ ERA