902 AXNT20 KNHC 202343 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Mon Aug 21 2023 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2230 UTC. ...SPECIAL FEATURES... Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details on these special features. ...TROPICAL STORM EMILY (AL07)... The center of Tropical Storm Emily, at 2100 UTC, is near 20.2N 39.4W, moving W-NW, or about 300 degrees, at 9 knots. The estimated minimum central pressure remains 1001 mb. The maximum sustained wind speed is 45 knots with gusts to 55 knots. Tropical storm force winds are within 160 nm of the center in the NE quadrant, and within 100 nm of the center in the NW quadrant. The sea heights of 12 feet or greater are within 150 nm nm SW, and 120 nm NW quadrants, with peak seas estimated at 20 ft. Scattered to numerous moderate to strong convection is within 300 nm of the center across the NE quadrant. Please, refer to the following website, www.hurricanes.gov, for more information and forecasts. ...TROPICAL DEPRESSION SIX (AL06)... The center of TROPICAL DEPRESSION SIX, at 2100 UTC, is near 16.6N 54.7W, moving W-NW, or 285 degrees, at 8 knots. The estimated minimum central pressure is 1008 mb. The maximum sustained wind speed is 30 knots with gusts to 40 knots. The sea heights range from 8 feet to 12 feet within 300 nm of the center in the N semicircle. Numerous strong convection is within 90 nm across the NE quadrant, while scattered moderate to strong convection is within 180 nm across the W semicircle. Please, refer to the following website, www.hurricanes.gov, for more information and forecasts. ...Tropical Storm Franklin (AL08)... The center of newly formed Tropical Storm Franklin is centered near 14.6N 67.1W, at 210 UTC, moving W-NW, or 290 degrees, at 12 kt. Minimum central pressure is 1002 mb. Maximum sustained wind is 40 kt with gusts to 50 kt. Seas of 8-11 ft are found within 180 nm across the north semicircle. numerous strong is from 12N to 15N between 65W and 67W. Scattered moderate to strong is from 11N to 18N between 54W and 64W. Scattered to numerous strong convection is noted from 12.5N to 16.5N between 62W and 68W. Please, refer to the following website, www.hurricanes.gov, for more information and forecasts. ...INVEST 91L IN THE EASTERN GULF OF MEXICO... Showers and thunderstorms associated with an area of disturbed weather in the eastern Gulf of Mexico have increased this afternoon, and cover an area from 22.5N to 28N east of 88W. Late morning satellite derived scatterometer winds showed a broad surface trough there, with moderate to locally fresh E to NE winds. Seas there are currently 3 to 5 ft. Additional development of this system is possible as it moves westward 15 to 20 mph. It is possible that a tropical depression may form, as the weather system approaches the western Gulf of Mexico coastline by Tuesday. The chance of formation into a tropical cyclone during the next 48 hours is medium. Please, refer to the following website, www.hurricanes.gov, for more information and forecasts. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 23W, from 21N southward, moving westward 10 to 15 knots. Scattered moderate to strong convection is noted from 08.5N to 17.5N between Africa and 25W. The environmental conditions appear to be conducive for gradual development of this weather system. It is possible that a tropical depression may form later this week. The weather system is forecast to move west-northwestward through the eastern tropical Atlantic Ocean during the next few days. Please, refer to the following website, www.hurricanes.gov, for more information. A Caribbean Sea tropical wave is along 88W, from 22N southward, moving westward 10 to 15 knots. Scattered moderate to strong convection is from 15.5N southward between 81W and 85W. ...MONSOON TROUGH/ITCZ... The monsoon exits the African coast near 13N17W to 12.5N21W to 16N32W. Scattered moderate to strong convection is within 120 nm north of the monsoon trough between 27W and 31W. Scattered moderate convection is seen from 08.5N to 12N between 37W and 49W. ...GULF OF MEXICO... Please, read the SPECIAL FEATURES section, for details about the GULF OF MEXICO developing low pressure center. A north-to-south oriented surface trough along 85W-86W was depicted by late morning scatterometer data. Light to gentle NE to E winds prevail to the west of this area, where seas are 2-3 ft. Widely scattered moderate convection dots most of the Gulf west of 88W. Moderate to fresh winds prevail over the eastern Gulf associated with a surface trough off the west coast of Florida. This system is expected to move westward at about 15 to 20 kt, and bring freshening winds and building seas into the western Gulf over the next 48 hours. A tropical depression could form as it approaches the western Gulf of Mexico coastline by Tuesday. This system has a medium chance of development in 48 hours. Regardless of development, active weather and rough seas can be expected in the central and western Gulf on Mon through Tue. ...CARIBBEAN SEA... Please, refer to the SPECIAL FEATURES section, for details about Tropical Storm Franklin. Please, refer to the TROPICAL WAVES section, for details about the Caribbean tropical wave. High pressure across the NW Atlantic is contributing to the pressure gradient across the northern semicircle of Franklin. Fresh to strong trade winds across the periphery of Franklin are N of 14N between 63W and 72W. Seas in this area are 6 to 9 ft and increase to 11 ft N of Franklin. To the W of 72W moderate to locally fresh NE to E trade winds prevail to 82W. Seas there are 4 to 7 ft, and highest offshore of NW Colombia. Light winds and seas less than 3 ft prevail across the NW Caribbean. Tropical Storm Franklin is forecast to move to 15.0N 68.9W Mon morning, 15.4N 70.7W Mon afternoon, 15.8N 71.5W Tue morning, 17.2N 71.5W Tue afternoon, inland across Hispaniola near 19.1N 71.1W Wed morning, and 21.0N 70.6W Wed afternoon. Franklin will then move N-NE across the Atlantic and strengthen to a hurricane near 23.9N 67.5W Thu afternoon. Rough to very rough seas can be expected through Wed in the eastern and central Caribbean. ...ATLANTIC OCEAN... Please, refer to the SPECIAL FEATURES section, for details about TROPICAL STORM EMILY and TROPICAL DEPRESSION SIX. An upper level cyclone near 28N58W is producing widely scattered moderate convection from 27N to 33N between 57W and 63W. To the W, scattered to locally numerous convection affecting the Bahamas and much of south and central Florida the past 24 hours has shifted westward into the Gulf of Mexico and across the Florida Peninsula. Scattered moderate to strong convection extends from just W of Andros Island, Bahamas, and across the Florida Keys and southern Florida. Gentle to moderate NE to E winds prevail across the Atlantic N of Franklin and west of 55W, except for fresh to strong winds along the N coast of Hispaniola into the Windward Passage. Seas are 4 to 6 ft across these open Atlantic waters, and 5-7 ft N of Hispaniola. The subtropical ridge covers the rest of the Atlantic Ocean, but is disrupted to some extent by TD Six and Emily. This is yielding gentle to moderate winds well N of both these systems to 31N, and light to moderate mainly southerly winds to the S of both these systems. The sea heights range from 4 feet to 6 feet to the N of the pair of tropical systems, and 5 to 6 ft to the south. Tropical Storm Franklin is expected to turn northward across Hispaniola on Wed and then enter the Atlantic, where it will strengthen to a hurricane near 23.9N 67.5W Thu afternoon. Meanwhile, Tropical Depression Six will become a remnant low and move to 16.7N 56.1W Mon morning, and dissipate Mon afternoon. Fresh to strong tradewinds will pulse off Hispaniola and the Windward Passage each evening through Tue night. $$ Stripling