000 AXNT20 KNHC 191742 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 142 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 1200 UTC surface analysis and satellite imagery through 1715 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 gust to gale-force winds 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 is added to the 1200 UTC analysis/surface map based on satellite imagery and scatterometer data. The wave axis extends from 12N23W to 04N24W. Scattered moderate convection is mainly ahead of the wave axis from 04N-08N between 23W and 26W. A tropical wave axis extends from 15N53W to 07N45W, moving west at 15-20 KT. Moisture within the wave environment has decreased as noted in TPW imagery. A tropical wave previously located across central Venezuela is no longer identifiable. A tropical axis extends from 18N81W to 09N81.5W, moving west at 5-10 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 axis from 09N- 15N between 79W-83W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough enters the tropical Atlantic through Guinea near 10N14W and continues to 08N21W. The ITCZ extends from 05N29W to 01N40W to 00N50W. Outside of the convection associated with the tropical wave, no significant convective activity is noted. ...DISCUSSION... GULF OF MEXICO... High pressure of 1022 mb located over the SE CONUS extends a ridge across the Gulf waters producing moderate to fresh E to SE winds across most of the basin. Areas of fog were noted over the NW Gulf under the influence of a SE wind flow. 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 SE Gulf and extends from 25N86W to the NE Yucatan Peninsula. This trough will gradually shift westward. 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 south of Cuba and west of Jamaica as well as over the SW Caribbean, mainly S of 16N and between 80W and the Atlantic coast of Nicaragua. Abundant tropical moisture is forecast to persist over the western caribbean on Saturday. High pressure located N of the area combined with the Colombian/Panamanian low is 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 SE 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 27N59W to 20N61W. 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 $$ GR