000 AXNT20 KNHC 192320 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 720 PM EDT Fri May 19 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 2315 UTC. ...SPECIAL FEATURES... Please refer to the METEO-FRANCE High Seas Forecast, listed on the website: WWW.METEOFRANCE.COM/PREVISIONS-METEO-MARINE/BULLETIN/ GRANDLARGE/METAREA2. Frequent wind gusts to gale-force are forecast for the area of AGADIR. These conditions will dissipate during the next 6-12 hours. An earlier scatterometer pass confirmed the presence of these winds. ...TROPICAL WAVES... A tropical wave axis extends from 12N23W to 04N24W, moving west at 10-15 kt. Isolated showers prevail along the wave's axis between 23W- 26W. A tropical wave axis extends from 14N53W to 07N53W, moving west at 10-15 kt. Moisture within the wave's environment has decreased significantly as noted in TPW imagery. No convection is related to this wave at this time. A tropical axis extends from 18N81W to 10N81W, moving west at 10-15 kt. The wave remains embedded within an area of deep-layer moisture as depicted in TPW imagery. Scattered moderate convection is observed on either side of the wave's axis from 11N-15N between 80W-84W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough enters the tropical Atlantic through Guinea near 10N14W and continues to 07N21W. The ITCZ extends west of a tropical wave from 06N26W to 03N38W to 00N50W. Outside of the convection associated with the tropical wave, no significant convective activity is noted at this time. ...DISCUSSION... GULF OF MEXICO... A broad area of high pressure prevails across the southeast CONUS and Atlantic ocean, extending across the basin. This pattern is producing moderate to fresh southeasterly winds across most of the area. Fresh to locally strong easterly winds are noted just north of the Yucatan Peninsula in association with a thermal trough. A surface trough is analyzed over the southeast Gulf and extends from 23N86W to the northeast coast of the Yucatan Peninsula. This trough is expected to gradually shift westward during the next 24 hours. Lower pressures prevail across Mexico and the far west Gulf waters. Aloft, a short-wave trough is noted across the north-central Gulf and is expected to cross north Florida on Saturday. On this day, zonal flow will dominate the Gulf region. The ridge will persist through Sunday with little change in the weather pattern. A weak cold front is forecast to move off the Texas coast by Sunday night. CARIBBEAN SEA... As previously mentioned, a tropical wave is moving across the western Caribbean. Please refer to the TROPICAL WAVE section above for details. A cut-off upper-level low continues to spin over the Cayman Islands. A sharp trough extends from the low toward the Gulf of Honduras and northern Central America. This system has been responsible for large areas of strong thunderstorms across the north-central Caribbean over the past several days. Just south of the low is the axis of above mentioned tropical wave. The combination of these two features is producing scattered showers and a few thunderstorms affecting portions of Cuba, Cayman Islands and Jamaica, as well as portions of Nicaragua, Costa Rica and Panama. Abundant tropical moisture is forecast to persist over the western Caribbean during the next 24 hours. High pressure located north of the area combined with the Colombian/Panamanian low are supporting strong to near gale-force winds over the south-central Caribbean, including the Gulf of Venezuela. A recent scatterometer pass indicate fresh to strong winds across the remainder of the central Caribbean, with fresh southeasterly winds just north of Jamaica. Fresh to strong trades will persist over the central Caribbean during the upcoming weekend. ...HISPANIOLA... Upper-level flow has become more zonal across the island with a break in the heavy rainfall from the past few days. Moisture is forecast to diminish over the upcoming weekend as the upper- level trough continues to drift eastward and the wind flow turns more to the NW. As a result, expect scattered showers and isolated thunderstorms due to local effects. ...ATLANTIC OCEAN... A Gale Warning is in effect for the far east Atlantic waters. Please refer to the SPECIAL FEATURES section above for details. A ridge, with several high pressure centers along 31N/32N, dominates the Atlantic Ocean. A surface trough extends from 26N60W to 21N62W. A recent scatterometer pass shows pretty well the wind shift associated with this trough. Scattered showers are near the trough axis. This feature is ahead of an upper-level trough that extends from 31N61W to central Cuba into the cut-off low over the Caribbean. Abundant mid-upper level moisture persists ahead of this upper trough forecast to drift eastward. For additional information please visit http://www.hurricanes.gov/marine $$ ERA