000 AXNT20 KNHC 221043 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Thu Sep 22 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 0600 UTC surface analysis and satellite imagery through 1050 UTC. ...SPECIAL FEATURES... Major Hurricane Fiona is centered near 27.4N 70.6W at 22/0900 UTC or 420 nm SW of Bermuda moving NNE at 11 kt. Estimated minimum central pressure is 934 mb. Maximum sustained wind speed is 115 kt with gusts to 140 kt. Numerous moderate isolated strong convection is from 25N to 33N between 63W and 73W. Peak seas near Fiona are currently estimated to be 51 ft. On the forecast track, the center of Fiona will pass just to the west of Bermuda tonight, approach Nova Scotia on Friday, and move across Nova Scotia and into the Gulf of St. Lawrence on Saturday. Little change in strength is expected through tonight. Some weakening is expected to begin on Friday, but Fiona is forecast to still be producing hurricane-force winds Friday night and Saturday after it has become post-tropical. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Tropical Storm Gaston is centered near 40.3N 35.4W at 22/0900 UTC or 330 nm WNW of Faial Island In The Central Azores moving ENE at 15 kt. Estimated minimum central pressure is 999 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Scattered moderate and isolated strong convection is from 39N to 46N between 27W and 38W. On the forecast track, the center of Gaston will move near or over portions of the Azores on Friday. Gradual weakening is expected over the next few days. Please read the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. A tropical wave is in the SE Caribbean with axis near 64W S of 17N, moving W at 15 kt. Scattered moderate convection is S of 15N between 59W and 69W. The disturbance is forecast to move west- northwestward across the eastern Caribbean Sea during the next day or two, and be over the central Caribbean Sea this weekend. Regardless of development, locally heavy rainfall and gusty winds are likely to affect the Windward Islands this morning. These impacts are likely to spread to northern Venezuela, northeastern Colombia, and the ABC island chain during the next couple of days. There is a high chance of tropical cyclone formation during the next 48 hours. Please refer to the latest Atlantic Tropical Weather Outlook at hurricanes.gov for more details. A tropical wave coming off the west coast of Africa extends from 05N to 20N with axis near 16W, moving W at 10 kt. Scattered moderate convection is from 10N to 16N between 14W and 20W. The tropical wave is forecast to move over the far eastern Atlantic waters later today. Thereafter, environmental conditions are forecast to be conducive for some development, and a tropical depression could form by this weekend while the system moves slowly northward, between west Africa and the Cabo Verde Islands. The chance of tropical cyclone formation during the next 48 hours is medium. ...TROPICAL WAVES... Please see the Special Features section above for a full description of the two tropical waves in the basin currently. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from 14N17W to 10N22W to a 1010 mb low near 10N33W to 09N37W. The ITCZ begins near 09N38W to 10N56W. Aside from the convection associated with the E Atlantic tropical wave, scattered moderate convection associated with a 1010 mb low is from 10N to 15N between 30W and 37W. GULF OF MEXICO... High pressure prevails over the Gulf coast states. Gentle to locally moderate N to NE winds prevail over the northern half and far SW gulf, with light to gentle winds elsewhere. Seas are in the 2-4 ft range basin-wide. For the forecast, a relatively weak pressure gradient across the region will support mainly light to gentle variable winds through Mon morning with locally moderate winds during this period. A tropical wave, currently over the eastern Caribbean along 64W, is likely to develop into a tropical cyclone while over the Caribbean Sea, then approach the Yucatan Channel late Mon before moving into the Gulf of Mexico by the middle of next week. In advance of this system, moderate to fresh NE winds will develop over the southern half of the basin by Mon afternoon. CARIBBEAN SEA... Please see the Special Features section above for details on a strong tropical wave over the SE Caribbean Sea which has a high chance of developing into a tropical cyclone within the next 48 hours. Otherwise, light to gentle variable winds are across the remainder of the basin, west of 68W with 1-3 ft seas. For the forecast, the tropical wave along 64W is likely to develop into a tropical cyclone by the time it reaches the central or western Caribbean in the next couple of days. There is a chance it could strengthen as it approaches the Yucatan Channel late Mon. Therefore, increasing winds, seas and squalls can be expected with this system as it moves farther west in the basin. ATLANTIC OCEAN... Please read the Special Features section above for information about Major Hurricane Fiona. The area of strong winds and high seas associated with Fiona currently extends from 22N-31N between 65W-76W. Fresh SE winds extend eastward to 60W and southeastward to the Caribbean. An area of convection is noted over Hispaniola and adjacent waters from 19N-22N between 68W-74W. High pressure ridging prevails over the remainder of the basin, to the east of Fiona. Moderate trades prevail between 22W-60W with seas of 3-6 ft. Fresh winds and seas to 7 ft are near the Windward Islands due to the aforementioned tropical wave. The latest ASCAT data shows fresh to strong NE winds off the coasts of Morocco and Western Sahara, where seas are likely 5-7 ft. For the forecast W of 55W, Hurricane Fiona will move to 29.3N 69.7W this afternoon, 32.5N 66.9W Fri morning, 37.4N 63.3W Fri afternoon, and further N of the area near 34.8N 65.1W by Fri morning. Swells generated by Fiona will continue to spread westward across the SW Atlantic toward the NW Bahamas and the E coast of the United States during the next couple of days. The swells could cause life-threatening surf and rip current conditions. A cold front will drop south over the north waters early on Fri through Sat night followed by fresh northeast winds and building seas. High pressure will build in behind the cold front. $$ Ramos