000 AXNT20 KNHC 231715 TWDAT Based on 1200 UTC surface analysis and satellite imagery through 1700 UTC. ...SPECIAL FEATURES... Tropical Storm Don is centered near 43.9N 47.8W at 23/1500 UTC or 280 nm SE of Cape Race Newfoundland moving NNE at 14 kt. Estimated minimum central pressure is 993 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Visible and infrared satellite imagery still show a well-defined center, with a convective band mainly concentrated on the northern and eastern side of the system. Don should begin to rapidly weaken as it moves over very cool waters with increasing vertical wind shear. Simulated satellite imagery from both the GFS and ECMWF models suggest that it should lose any remaining deep convection within 24 hours and become a post-tropical cyclone. The storm should turn northeastward later today and east-northeastward Monday. Further weakening is forecast, and Don is likely to lose tropical characteristics tonight or tomorrow. Please read the latest HIGH SEAS FORECAST issued by National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest T.S. Don Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave has its axis along 24W from 04N to 20N. It is moving westward at 10-15 kt. Scattered moderate convection is seen from 05N to 11N and between 17W-28W. While, dry air to the north of the wave is inhibiting convection development. A central Atlantic tropical wave has its axis along 38W from 04N to 20N, moving westward at 10-15 kt. No significant convection is seen associated with this wave. ...MONSOON TROUGH/ITCZ... The monsoon trough axis enters the Atlantic through the coast of Mauritania near 20N17W and continues southwestward to 11N24W and to 12N35W to low pressure (Invest 95L) near 10N46.1W and to 10N50W. No significant convection is depicted in association with the trough. Please see the TROPICAL WAVE and ATLANTIC OCEAN sections for convection in the area. ...GULF OF MEXICO... A pre-frontal trough is moving across the northern Gulf in association with a stationary front that is draped across the southern United States. This pre-frontal trough is producing a broken line of scattered to isolated strong convection that extends from the northwest coast of Florida (29N82W) all the way to the shore waters near the U.S./Mexico Country line. This activity is forecast to persist throughout the afternoon hours as it moves mainly east-southeast. However, convection intensity and coverage may decrease during that time. Farther south, scattered showers and thunderstorms are seen in the western Bay of Campeche in association to a surface trough. The remainder of the Gulf remains under the western periphery of the subtropical ridge positioned near the Azores. Outside of convection, moderate or weaker winds and seas of 1-3 ft are prevalent across the basin. For the forecast, weak high pressure centered over the eastern Gulf will change little early this week. This will support mainly gentle to moderate winds, except over the eastern Bay of Campeche where winds will be enhanced by a thermal trough that will emerge off the Yucatan Peninsula nightly. ...CARIBBEAN SEA... Scattered showers and thunderstorms are seen in the off shores water of Nicaragua, Costa Rica, and Panama. The remainder of the basin is under the influence of a subtropical ridge positioned near the Azores. Saharan dust covers most of the Caribbean, resulting in drier conditions, above normal temperatures and reduced visibility. The pressure gradient between the aforementioned ridge and lower pressures in northern South America continues to support fresh to strong easterly trade winds in the central Caribbean and the Gulf of Honduras. The strongest winds are occurring off northern Colombia. Over the rest of the Caribbean, moderate or weaker winds prevail. Seas are 7-9 ft over the central Caribbean and the Gulf of Honduras and mostly 3-6 ft elsewhere. For the forecast, the pressure gradient between the Bermuda High and lower pressure over Central America and northern South America will maintain strong trades across the central Caribbean today. Winds should diminish slightly to fresh to strong Mon into Wed night. Fresh to locally strong trades will develop over the Gulf of Honduras this evening and diminish Mon night. Low pressure over the tropical N Atlantic well east of the forecast waters is expected to weaken to a trough during the early part of the week as it approaches the Lesser Antilles. Some increase in winds and seas may accompany the trough. ...ATLANTIC OCEAN... Please see the SPECIAL FEATURES section for information on Tropical Storm Don in the north-central Atlantic. A 1012 mb low pressure system, designated as Invest 95L, is located near 10.6N46.1W. Shower activity continues to be limited in association with this low. Although environmental conditions are only forecast to be marginally conducive for some gradual development, this system could still become a tropical depression during the next few days while it moves westward across the tropical Atlantic and eastern Caribbean Sea. Unfavorable upper-level winds are forecast when the system moves into the central Caribbean around midweek, decreasing the chances of formation. Interests in the Lesser Antilles should monitor the progress of this system. This low has a low chance of development in the next 48 hours. Please, refer to the latest Tropical Weather Outlook at www.hurricanes.gov for more details. Scattered moderate convection is occurring from 25N to 30N between 65W-70W. The rest of the western Atlantic (west of 55W) remains under the western periphery of the subtropical ridge positioned near the Azores. Moderate or weaker winds and generally seas of 3-5 ft continue to the west of 55W. Over the remainder of the tropical Atlantic, the pattern is dominated by a 1031 mb high pressure near the Azores. The strong pressure gradient between the aforementioned ridge and lower pressures in NW Africa supports fresh to near gale-force northerly winds in the eastern Atlantic, mainly north of 20N and east of 35W. This was confirmed by a resent scatterometer pass. The strongest winds are noted north of 25N and east of 21W. Seas in the affected area are 6-8 ft. Moderate or weaker winds and slight to moderate seas are present over the remainder of the tropical Atlantic. For the forecast west of 55W, weak high pressure over the area will change little during the next few days. Fresh trades are likely to pulse nightly N just N of Hispaniola and over the Windward Passage. Elsewhere across forecast waters, winds will be moderate or weaker over most of the western half of the area with mostly moderate to locally fresh speeds elsewhere. $$ KRV