000 AXNT20 KNHC 020003 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 803 PM EDT Sat Jul 1 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 1800 UTC surface analysis and satellite imagery through 2345 UTC. ...SPECIAL FEATURES... ...Meteo-France Gale Warning... Gale-force N to NE winds will continue through tonight over the area of AGADIR. For more details, please refer to the METEO-FRANCE High Seas Forecast listed on the website: WWW.METEOFRANCE.COM/PREVISIONS-METEO- MARINE/BULLETIN/ GRANDLARGE/METAREA2. ...Caribbean Gale Warning... A stronger pressure gradient over the south central Caribbean is supporting strong to gale-force winds from 11N to 13N between 73W and 77W. These conditions will continue through Sunday morning. For more details, please refer to the High Seas Forecast product under AWIPS/WMO headers HSFAT2/FZNT02 KNHC. ...TROPICAL WAVES... A tropical wave came off the coast of Africa ealier today. Its axis extends from 17N17W to 06N15W and it has been moving at 5-10 kt within the last 24 hours. The wave is in a region of favorable wind shear, and is in a moderate moist environment with patches of dry air according to CIRA LPW imagery. Shallow moisture and upper level diffluence support scattered showers from 04N to 14N E of 20W. A tropical wave is in the E Atlc with axis extending from 15N27W to 04N31W, moving W at 10 kt within the last 24 hours. The wave is in a region of favorable wind shear, and is in a moderate moist environment with patches of dry air according to CIRA LPW imagery. Satellite enhanced imagery show Saharan dry air and dust intrusion in the wave environment. Shallow moisture and upper level diffluence support scattered to isolated showers from 04N to 13N between 23W and 34W. A tropical wave is just E of the Windward Islands with axis extending from 15N58W to 05N60W, moving W at 20 kt within the last 24 hours. The wave is in a region of neutral to favorable wind shear S of 16N, and is in a moderate moist environment with patches of dry air according to CIRA LPW imagery. Shallow moisture and upper level diffluence support scattered heavy showers and isolated tstms S of 16N between 57W and 63W. A tropical wave is in the W Caribbean with axis extending from 18N84W to 07N85W, moving W at 20 kt within the last 24 hours. The wave is in a region of unfavorable wind shear from 15N-20N. However, the CIRA LPW imagery show abundant moisture associated with this wave that supports isolated showers S of 21N W of 81W. Numerous heavy showers and scattered tstms with possible gusty winds are inland Central America countries, such as Guatemala, Belize, Honduras and Nicaragua. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from the west coast of Africa near 11N15W to 09N20W to 08N26W. The Intertropical Convergence Zone extends from 08N34W to 06N50W to 08N58W. For convection information see the tropical waves section above. ...DISCUSSION... GULF OF MEXICO... A broad upper level ridge is centered in northern Florida while an upper level low is over the central Bahamas. Diffluent flow between these two upper level features along with abundant moisture across the Florida Peninsula and adjacent waters is supporting scattered heavy showers and tstms with possible gusty winds across the central and SW portions of the Peninsula and Gulf waters E of 85W. Shower activity over this region is forecast to continuem through early Sunday morning. Isolated showers are in the SW basin S of 23N W of 94W being supported by shallow moisture and another region of upper level diffluence in that area. Otherwise, surface ridging prevails over the basin being anchored by a 1020 mb high near 29N87W, which provides light and gentle variable flow E of 91W, and mainly light to moderate SE winds W of 91W. Little change in the current synoptic pattern is expected during the next two days. CARIBBEAN SEA... A tropical wave is moving over the NW Caribbean waters and across central America where is supporting numerous heavy showers, tstms and possible gusty winds. However, unfavorable wind shear S of 21N over this region of the basin, only allow for scattered to isolated showers. Abundant moisture associated with this wave along with upper level diffluent between a broad ridge centered in northern Florida and a low over the central Bahamas support heavy showers, tstms and possible gusty winds along southern Cuba and adjacent waters. Heavy showers and scattered tstms are over Haiti and the western half of Dominican Republic supported by upper level divergence between the low over the Bahamas and a ridge across the E Caribbean centered just E of the Windward Islands. A tropical wave just E of the Windward Islands will move into the SE Caribbean tonight. This wave is already supporting scattered to isolated showers across the Islands and the SE basin S of 15N E of 68W. See the Tropical Waves section for further details. Otherwise, a gale warning continues for south-central Caribbean waters. See special features for more information. ...HISPANIOLA... Heavy showers and scattered tstms are over Haiti and the western half of Dominican Republic supported by upper level divergence between a low over the Bahamas and a ridge across the E Caribbean centered just E of the Windward Islands. These showers are forecast to continue through Sunday morning. ATLANTIC OCEAN... Three tropical waves were analyzed over the basin. Refer to the Tropical Waves section above for details. A surface trough over the central Atlantic curving from 27N43W to 15N45W possess no significant convection. The remainder of the basin remains under the influence of a broad surface ridge, anchored by a 1034 mb high centered just northeast of the Azores. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos