000 AXNT20 KNHC 141803 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Wed Sep 14 2022 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 1200 UTC surface analysis and satellite imagery through 1700 UTC. Discussion updated at 0700 UTC to account for the increased tropical cyclone development potential described in the special features section. ...SPECIAL FEATURES... Newly formed Tropical Depression (TD) Seven is located near 16.6N 49.6W at 14/1500 UTC, about 700 nm east of the Leeward Islands and moving west at 12 kt. It has an estimate minimum central pressure of 1009 mb and maximum sustained winds are 30 kt with gusts to 40 kt. Seas are peaking at 10 to 12 ft near and northeast of the center. Numerous moderate convection is flaring up near and up to 100 nm NE and SE of the center. TD seven is expected to continue a general westward motion, which will bring it over the Leeward Islands on Fri, then near Puerto Rico and the Virgin Islands this weekend. Some strengthening is forecast and TD seven could become a tropical storm tonight or Thur. Residents and marine interests in these areas need to monitor this system closely. Please read the latest NHC Public Advisory at: https://www.nhc.noaa.gov/text/refresh/MIATCPAT2+shtml/141459.shtml? and the Forecast Advisory at: https://www.nhc.noaa.gov/text/refresh/MIATCMAT2+shtml/141458.shtml? ...TROPICAL WAVES... An eastern Atlantic tropical wave is just west of the Cabo Verde Islands near 29W from 20N southward, and moving west around 10 kt. Scattered moderate convection is observed from 12N to 18N between 26W and 33W. Moderate to fresh NE to ENE winds and seas of 6 to 8 ft are found near the northern half of the wave from 15N to 21N between 26W and 34W. A Caribbean tropical wave is near 76W from eastern Cuba southward across Jamaica to northwestern Colombia, and moving west at 5 to 10 kt. Scattered showers and isolated thunderstorms are occurring near Jamaica. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic along the coast of Gambia across 11N30W to 09N40W. Scattered showers and isolated thunderstorms are seen from 06N to 15N between the central African coast and 24W, and farther west from 05N to 08N between 37W and 42W. There is no ITCZ present based on this analysis. The eastern end of the East Pacific monsoon trough is triggering scattered showers and isolated thunderstorms across Panama and northwest Colombia, and nearby Caribbean waters. ...GULF OF MEXICO... A weak stationary front extends eastward from near Galveston, Texas to north of Tampa, Florida, then continues east- northeastward as a cold front across northern Florida. Widely scattered showers and isolated thunderstorms are present up to 50 nm along either side of this boundary. Aided by divergent flow aloft, two surface troughs: one off southwestern Florida and another one over the western Gulf are triggering scattered showers and thunderstorms over the Gulf waters south of the stationary front. Moderate to locally fresh ENE winds and seas of 2 to 4 ft exist north of the stationary front. South of the front, gentle to moderate E to SE winds and 1 to 3 ft seas prevail. For the forecast, the stationary front will gradually dissipate late this week. Afterward, high pressure will build over the southeast U.S. in the wake of the front, maintaining gentle to moderate easterly breezes and slight seas into the weekend. ...CARIBBEAN SEA... Please read the Special Features section at the beginning for more information on newly formed Tropical Depression Seven, which will impact the Leeward Islands and near Puerto Rico toward this weekend. A broad upper-level low north of the Panama-Colombia border near 13N78W is generating scattered showers and isolated thunderstorms over the northwestern basin, including the Yucatan Channel. Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for additional weather in the basin. Gentle to moderate with locally fresh easterly trades and 4 to 6 ft seas are present for the eastern and central basin. Mainly gentle E to SE trades and seas of 2 to 4 ft prevail for the western basin. For the forecast, Tropical Depression Seven is forecast to strengthen to a tropical storm this evening near 16.7N 51.5W, move to near 17N59W Fri morning, near 17.5N 64.5W Sat morning, and near 18N 68.5W Sun morning. Expect increasing winds and squalls over the NE Caribbean with this cyclone. Otherwise, winds and seas will increase somewhat starting tonight over the central Caribbean as high pressure builds north of the area in the wake of a tropical wave. Northerly swell moving through the Atlantic passages will gradually subside through tonight. ...ATLANTIC OCEAN... Please read the Special Features section at the beginning for more information on newly formed Tropical Depression Seven, which will impact the Leeward Islands and near Puerto Rico toward this weekend. A cold front stretches northeastward from near Daytona Beach, Florida to beyond 31N at 77W. A surface trough is south of this front near 28N76W. Together, these features are producing scattered showers and thunderstorms from the southeast Florida coast and central Bahamas northward to 31N. Another cold front reaches southwestward from west of the Azores across 31N40W to 29N44W, then continues as a stationary front to 27N50W. Scattered moderate convection is evident near and up to 80 nm south of this boundary. Convergent surface winds are causing scattered moderate convection east of the Leeward Islands from 14N to 17N between 53W and 60W, and farther southeast from 07N to 11N between 44W and 50W. The Atlantic ridge is supporting light to gentle winds and seas at 5 to 7 ft in northerly swell north of 24N between the northwest African coast and 70W. West of 70W, gentle to moderate southerly winds with 3 to 5 ft seas are found from the central Bahamas northward to 31N. Outside the influence of Tropical Depression Seven and the tropical wave west of the Cabo Verde Islands, gentle to moderate NNE to E trades and seas of 5 to 8 ft are seen from 12N to 24N between the central African coast and the southeast Bahamas/Lesser Antilles. Light to gentle with locally moderate monsoonal and southerly winds and seas at 4 to 6 ft prevail for the rest of the Atlantic Basin. For the forecast west of 55W, Tropical Depression Seven is forecast to strengthen to a tropical storm this evening near 16.7N 51.5W, move to near 17N59W Fri morning, near 17.5N 64.5W Sat morning, and near 18N 68.5W Sun morning. Expect increasing winds, seas and squalls near and north of the cyclone. Otherwise, moderate northerly swell east of the Bahamas is expected to subside through today, mainly west of 65W. Looking ahead, a cold front may move into the waters off northeast Florida and stall by the end of the week into the weekend. $$ Chan