000 AXNT20 KNHC 270551 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 151 AM EDT Sat May 27 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...TROPICAL WAVES... A tropical wave is in the eastern Atlc with axis extending from 11N22W to 01N22W, moving W at 15 kt. CIRA LPW imagery shows a moderate moist environment near the ITCZ with dry air in the Saharan Air Layer N of 10N. The 700 mb analysis shows a good wave reflection. Scattered showers are within 120 nm of the wave axis. A tropical wave is in the central Atlc with axis extending from 10N35W to 01N36W, moving W at 20 kt. CIRA LPW imagery shows a moderate moist environment near the ITCZ with dry air in the Saharan Air Layer N of 10N. The 700 mb analysis shows a good wave reflection along 38W. Scattered moderate convection is E of the wave axis from 05N-07N between 32W-35W. Scattered showers are within 120 nm of the remainder of the wave axis. A tropical wave is in the W Atlc with axis extending from 13N53W to 05N53W, moving W at 20 kt. This wave shows a well defined inverted-V surface reflection on satellite imagery. CIRA LPW imagery shows a moist environment. The 700 mb analysis shows a good wave reflection along 54W. Scattered moderate convection is W of the wave axis from 10N-12N between 53W-55W. Scattered showers are within 120 nm of the remainder of the wave axis. A tropical wave is just E of the Lesser Antilles with axis extending from 15N58W to 08N59W, moving W at 15 kt. Unfavorable wind shear and Saharan dry air across the wave environment is hindering convection at this time. There is a very pronounced 700 mb wave reflection however along 61W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough enters the tropical Atlantic near 10N14W and continues to 06N20W. The ITCZ extends between tropical waves from 06N25W to 05N33W. The ITCZ resumes again near 04N37W and extends to the coast of South America near 01N50W. Besides the convection associated with the tropical waves, scattered moderate convection is from 02N-07N between 15W-21W. ...DISCUSSION... GULF OF MEXICO... As of 0300 UTC, a 1019 mb high is located over the NE Gulf of Mexico near 28N84W. 5-10 kt anticyclonic winds are over the NE Gulf. 10-20 kt SE surface winds are over the W Gulf. In the upper levels, a ridge is over the Gulf with axis along 91W. Strong subsidence is over the Gulf, while upper level moisture is over Texas. Expect showers to advect into the Bay of Campeche over the next 24 hours. CARIBBEAN SEA... A tropical wave is just E of the Leeward Islands. See above. the monsoon trough extends over Costa Rica and Panama producing scattered moderate to strong convection. Further N, scattered moderate to isolated strong convection is along the coast of Nicaragua, and inland over Honduras. In the upper levels, a ridge is over the W Caribbean. An upper level trough is over the E Caribbean with strong subsidence. Expect over the next 24 hours for the tropical wave to enter the Caribbean. Also expect continued convection over the SW Caribbean, and Central America. ...HISPANIOLA... Saharan dust continue to be reported across the Island and is observed in satellite enhanced imagery. Water vapor imagery show strong subsidence over the Island, which is hindering convection at the moment. However, patches of low level moisture, embedded in the trade wind flow, could bring some cloudiness and isolated showers, particularly late Saturday into Sunday. ...ATLANTIC OCEAN... A cold front in the SW N Atlc long 31N67W to 29N72W. A stationary front continues to 25N80W. Scattered showers are over portions of the N Bahamas. A 1025 mb high is centered over the central Atlantic near 30N50W. A dissipating cold front is over the Canary Islands with scattered showers. Four tropical waves are over the tropical Atlantic. Please refer to the Tropical Waves section for more details. Saharan dry and dust is noted across much of the Atlantic Ocean between 10N-25N. Of note in the upper levels, a small upper level low is centered near 23N59W producing upper level diffluence with scattered showers from 20N-27N between 50W- 55W. Expect over the next 24 hours for the W Atlantic front to drift E, while a new cold front dips into the central Atlantic along 32N between 25W-40W with showers. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa