Tropical Weather Discussion
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000 AXNT20 KNHC 231110 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 710 AM EDT Tue May 23 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 1015 UTC. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 21W/22W from 12N southward, moving westward 15 knots. The area of cyclonic wind flow that is associated with this wave ranges between 19W and 23W, and the wave was placed in the middle of this range. Convective precipitation: scattered strong from 06N to 08N between 20W and 25W. An Atlantic Ocean tropical wave, that was along 39W/40W at 23/0000 UTC, was re-positioned in order to be along 55W/56W from 12N southward. The new position fit the Total Precipitable Water imagery, and the Diagnostics forecast data. Convective precipitation: any nearby precipitation is part of the ITCZ precipitation. widely scattered moderate to isolated strong from 07N to 09N between 49W and 55W. A Caribbean Sea tropical wave is along 75W/76W from 13N southward into Colombia, moving westward 10 to 15 knots. Convective precipitation: nothing significant. The wave is moving through an area of upper level SW wind flow. ...ITCZ/MONSOON TROUGH... The Monsoon Trough passes through coastal sections of Guinea- Bissau near 12N16W, to 10N17W and curving to 08N21W and 06N28W. The ITCZ continues from 06N28W to 05N38W and 05N44W. Convective precipitation: isolated moderate to widely scattered moderate and locally strong from 10N southward from 60W eastward, mostly within 60 nm on either side of 09N55W 07N35W 04N18W 05N01W. ...DISCUSSION... ...THE GULF OF MEXICO... Upper level NW wind flow spans the area. This NW wind flow is on the northwestern side of the NW Caribbean Sea trough. A stationary front is in the coastal waters/coastal plains between the Florida Pensacola to the Deep South of Texas. Convective precipitation: scattered strong from 27N northward from 92W eastward to Florida. ...VISIBILITY IN MILES, AND WEATHER, FOR THE OFFSHORE OIL PLATFORM SITES, THAT ARE IN THE AREA WHOSE BOUNDARIES ARE FROM 27N NORTHWARD AND FROM 88W WESTWARD... KVQT: 1 to 2 and mist. KHHV: 2 to 3 and mist. KVAF, KGUL, KGBK, KEIR, and KGRY: 3 to 5 and mist. KSPR: 2 to 3 and haze. VISIBILITY IN MILES, AND WEATHER, FOR THE COASTAL PLAINS OF THE U.S.A., FROM THE DEEP SOUTH OF TEXAS TO FLORIDA... TEXAS: rainshowers with thunder and some 3 to 4 miles in the Lower Valley. 3 miles and mist in Jasper. LOUISIANA: earlier heavy rain in the Lake Charles metropolitan area has ended for the moment. some light rain and drizzle around Lake Pontchartrain. MISSISSIPPI: rainshowers with thunder, and other areas of light rain, from Natchez to the Hattiesburg metropolitan area. ALABAMA: light rain in the southernmost parts of the state. rain in Mobile and Fort Rucker. FLORIDA: light rain from Tallahassee westward. Cross City: 3 to 5 and mist. ...THE CARIBBEAN SEA... An upper level trough extends from Cuba to eastern sections of Honduras/NE Nicaragua. Upper level SW and W wind flow covers the rest of the Caribbean Sea. Convective precipitation: Broken to overcast multilayered clouds and possible rainshowers cover the Caribbean Sea within 600 nm to the E and SE of the line that runs from SE Cuba toward NE Nicaragua. The monsoon trough is along 08N70W in NW Venezuela, across Colombia and Panama, beyond 10N86W near the western sections of Costa Rica. Convective precipitation: scattered to numerous from 11N southward to land, between 76W and 78W, reaching the Gulf of Uraba of Colombia at times. Other isolated moderate to locally strong from 13N southward from 76W westward. ...HISPANIOLA... Upper level SW and W wind flow moves across the area. SURFACE OBSERVATIONS...for Port-au-Prince in Haiti: MVFR. for the DOMINICAN REPUBLIC: Santo Domingo: VFR. La Romana and Punta Cana: VFR. Santiago: VFR. Puerto Plata: VFR. The GFS MODEL forecast for 250 mb shows that day one of the 48-hour forecast will start with a central Cuba-to-eastern Honduras/NE Nicaragua trough, and SW and W wind flow moving across Hispaniola. The trough will move to Hispaniola by the end of day one, bringing cyclonic wind flow to the area. The trough will move across and away from Hispaniola during and by the end of day two. Expect NW wind flow during and by the end of day two. The GFS MODEL forecast for 500 mb shows that an anticyclonic circulation center will be to the south of Hispaniola at the beginning of day one. SW wind flow will be present for the first 6 hours to 12 hours, followed by anticyclonic wind flow during the rest of day one. Expect anticyclonic wind flow during the first 12 hours to 18 hours of day two. Expect E to SE winds during the rest of day two. The GFS MODEL forecast for 700 mb shows that Hispaniola will be on the western end of an Atlantic Ocean-to- Hispaniola east-to- west oriented ridge. Expect southerly wind flow during the first 12 hours or so, followed by SE wind flow. ...THE ATLANTIC OCEAN... A central Atlantic Ocean upper level trough passes through 32N39W to 25N47W and 20N50W and 17N54W. The trough supports a cold front that passes through 32N36W to 27N54W and 31N64W. Convective precipitation: rainshowers are possible from 23N northward between 30W and 80W. A surface ridge passes through 32N22W to a 1020 mb high pressure center that is near 29N29W, to 22N42W 23N58W, to a 1021 mb high pressure center that is near 30N64W. Surface anticyclonic wind flow covers the Atlantic Ocean from 15N northward to the area of the cold front, between Africa and 80W. For additional information please visit $$ MT is the U.S. government's official web portal to all federal, state and local government web resources and services.