000 AXNT20 KNHC 241707 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Sat Sep 24 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. ...SPECIAL FEATURES... FIONA... Post-Tropical Cyclone Fiona is centered near 47.9N 61.3W at 24/1500 UTC or 90 nm WNW of Port Aux Basques Newfoundland moving N at 22 kt. Estimated minimum central pressure is 945 mb. Maximum sustained wind speed is 70 kt with gusts to 85 kt. Fiona has slowed down. On the forecast track, Fiona will move across the Gulf of St. Lawrence through tonight, across Labrador early Sun, then the Labrador Sea Sun night. Fiona continues to produce hurricane- force winds, heavy rains, storm surge, and rough marine conditions across Atlantic Canada and the surrounding waters. Seas are peaking to 60 ft near the center. Heavy rains from Fiona are expected to continue to impact portions of Nova Scotia, Prince Edward Island, and western Newfoundland today, persisting across eastern Quebec and Labrador into Sunday. This rainfall is expected to produce flooding, some of which could be significant. Large swells generated by Fiona are expected to cause life- threatening surf and rip current conditions along the coast of the northeast United States, Bermuda, and Atlantic Canada during the next couple of days. Please read the latest High Seas Forecast issued by the Ocean Prediction Center at website https://ocean.weather.gov/shtml/NFDHSFAT1.php and the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. GASTON... Tropical Storm Gaston is centered near 38.0N 30.8W at 24/1500 UTC or 100 nm WSW of Faial Island In The Central Azores moving WSW at 8 kt. Estimated minimum central pressure is 1001 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt, with very rough seas near the center. Gaston has now turned WSW, and this continued motion should keep Gaston moving through the western Azores today. Tropical storm conditions over the western and central Azores today should diminish today as Gaston moves away from the islands. Gaston is expected to produce heavy rainfall over the western and central Azores through Saturday. This rainfall may result in landslides and areas of flooding. Please read the latest High Seas Forecast issued by the Ocean Prediction Center at website https://ocean.weather.gov/shtml/NFDHSFAT1.php and the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. HERMINE... Tropical Storm Hermine is centered in the eastern Atlantic near 20.8N 20.8W at 24/1500 UTC or 340 nm NNE of the Cabo Verde Islands moving N at 7 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt with rough seas near and to the north of the center. Hermine remains strongly sheared with an exposed center to the southwest of scattered moderate to isolated strong convection. A northward motion will continue through tonight before a turn toward the left Sun. Some weakening expected Sun, and Hermine could become a remnant low on Mon. Please read the latest High Seas Forecast issued by Meteo-France at website http://weather/gmdss.org/ll.html and the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. IAN... Tropical Storm Ian is centered in the Caribbean Sea near 14.4N 75.2W at 24/1500 UTC or 230 nm SSE of Kingston Jamaica moving W at 13 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Seas are peaking at 8 to 10 ft near and NE of the center. Numerous moderate to scattered strong convection is noted from 12N to 17N between 73W and 78W. A generally westward motion is expected through tonight, followed by a turn to the NW Sun and NNW Mon as it moves across the northwestern Caribbean Sea. Strengthening is forecast over the next few days. Ian is expected to become a hurricane by late Sun and approaching western Cuba at or near major hurricane strength by Mon night. A W to WNW motion is expected through early Sun, followed by a NW turn late Sun, and a NNW turn by late Mon. On this forecast track, Ian will move across the central Caribbean Sea today, pass SW of Jamaica on Sun, and then very close to the Cayman Islands Sun night through early Mon. Ian is likely to approach western Cuba Mon. Strengthening is forecast for the next few days, and Ian is likely to become a hurricane by Sun night. Ian is expected to produce heavy rainfall, flash flooding, and possible mudslides in areas of higher terrain, particularly over Jamaica and Cuba. Limited flash and urban flooding is possible with rainfall across the Florida Keys and Florida peninsula through mid next week. Ian is forecast to move near or over western Cuba and approach the west coast of the Florida peninsula at or near major hurricane strength early next week, where there is increasing confidence in multiple life-threatening hazards: storm surge, hurricane-force winds and rainfall flooding. While it is too soon to determine the exact magnitude and location of these hazards, residents in Cuba, the Florida Keys, and the Florida peninsula should ensure they have their hurricane plan in place, follow any advice given by local officials, and closely monitor updates to the forecast. Please consult products from your local weather office for more details. 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 WAVES... There are no tropical waves present based on the latest analysis. ...MONSOON TROUGH/ITCZ... A monsoon trough extends west-southwestward from near the Cabo Verde Islands at 15N24W through a 1009 mb low centered near 12N36W to 09N42W. An ITCZ then continues from 09N42W to 08N60W. Scattered moderate convection is noted within 120 nm in the NW semicircle of the low near 12N36W. ...GULF OF MEXICO... Please refer to the Special Features section above on Tropical Storm Ian, which is anticipated to impact the eastern Gulf early next week. A stationary front extends over the eastern Gulf, from near Port Charlotte, Florida to 27N85W. A few showers and thunderstorms are active about 90 nm south of Panama City, Florida, associated with a weak developing trough. Isolated showers and thunderstorms are also active in the far southwest Gulf. A weak pressure pattern continues across the basin, supporting light breezes and slight seas in most areas. For the forecast, conditions will begin to deteriorate across the eastern Gulf of Mexico by early next week as the center of Ian emerges from Cuba. Gulf coast residents and mariners in the region should follow the latest advisories over the next several days on Ian and make preparations accordingly. ...CARIBBEAN SEA... Please refer to the Special Features section above on Tropical Storm Ian moving across the basin. Outside of the main impacts of T.S. Ian across the central Caribbean, no significant shower or thunderstorm activity is evident at this time. Moderate E to SE winds and slight to moderate seas are observed across the eastern Caribbean, and light to gentle NE breezes and slight seas are noted over the northeast Caribbean. For the forecast, Ian will move to 14.5N 76.8W this evening, 15.5N 78.9W Sun morning, strengthen to a hurricane near 17.0N 80.7W Sun evening, 18.8N 82.3W Mon morning, 20.7N 83.4W Mon evening, and 22.7N 84.1W Tue morning. Ian will change little in intensity as it moves near 26.0N 83.9W by early Wed. Deteriorating marine conditions can be expected near the track of Ian, including the central Caribbean through early Sun, and portions of the northwest Caribbean later on Sun through Tue. Heavy rainfall and hazardous marine conditions will impact waters near Jamaica, the Cayman Islands and Cuba. ...ATLANTIC OCEAN... Please refer to the Special Features section above on Post- tropical Cyclone Fiona and Tropical Storms Gaston and Hermine in the Atlantic Basin. A weak cold front extends from SE of Bermuda near 31N61W to 27N72W, where it becomes stationary and extends across the northern Bahamas to near Jupiter Inlet, Florida. Scattered moderate convection is noted from 120 to 150 nm of this boundary north of 26N. A few showers and thunderstorms are also evident along the stationary boundary over the northern Bahamas. Refer to the Monsoon Trough/ITCZ section above for additional convection in the Atlantic Basin. Buoy and altimeter satellite data indicate 8 to 10 ft seas mainly north of 26N between 60W and 75W. This is mainly northerly swell associated with the passage of Fiona across the western Atlantic. Elsewhere, outside of the main areas of impact associated with Hermine, mostly gentle to moderate trade winds and moderate seas are noted across the basin. For the forecast W of 55W, swells from extratropical cyclone Fiona continue across the forecast waters N of 27N and W of 55W. This swell will continue to propagate eastward while dissipating. Conditions are expected to improve by Mon morning. Tropical Storm Ian is near 14.4N 75.2W 1003 mb at 11 AM EDT moving W at 13 kt. Maximum sustained winds 40 kt gusts 50 kt. Ian will move to 14.5N 76.8W this evening, 15.5N 78.9W Sun morning, strengthen to a hurricane near 17.0N 80.7W Sun evening, 18.8N 82.3W Mon morning, 20.7N 83.4W Mon evening, and 22.7N 84.1W Tue morning. Ian will change little in intensity as it moves near 26.0N 83.9W by early Wed. Impacts from Ian may impact areas offshore Florida early next week. $$ Christensen