TRACKING THE TROPICS


TROPICS WATCH


Gulf
Atlantic

For the North Atlantic, Caribbean Sea and the Gulf of Mexico:

Active Systems: The National Hurricane Center is issuing advisories on Post-Tropical Cyclone Fiona, currently in the Gulf of St. Lawrence, on Tropical Storm Gaston, located near the central Azores, on Tropical Storm Ian, located over the central Caribbean Sea, and on Tropical Storm Hermine, located over the far eastern Atlantic.

Central Tropical Atlantic: Showers and thunderstorms remain disorganized in association with a broad area of low pressure located several hundred miles west-southwest of the Cabo Verde Islands. Despite unfavorable upper-level winds, some slow development of this system is possible over the next several days while it drifts northwestward or northward over the central tropical Atlantic. * Formation chance through 48 hours, low, 20 percent. * Formation chance through 5 days, low, 30 percent.

Public Advisories on Tropical Storm Hermine are issued under WMO header WTNT35 KNHC and under AWIPS header MIATCPAT5. Forecast/Advisories on Tropical Storm Hermine are issued under WMO header WTNT25 KNHC and under AWIPS header MIATCMAT5.

Posted 4 hours ago by NHC Forecaster Forecaster Bucci

Special Features

Fiona

Post-Tropical Cyclone Fiona is centered near 46.0N 61.0W at 24/0900 UTC or 140 nm NE of Halifax Nova Scotia moving N at 23 kt. Estimated minimum central pressure is 931 mb. Maximum sustained wind speed is 80 kt with gusts to 100 kt. Seas are peaking to 63 ft near the center. On the forecast track, Fiona will move across the Gulf of St. Lawrence this morning, Labrador today and tonight, then the Labrador Sea into Sun. Dangerous storm surge is expected along the coast of Atlantic Canada near the path of Fiona. Large swells generated by Fiona are affecting Atlantic Canada, the east coast of the United States, Bermuda and northwestern Bahamas. The swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office.

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 38.6N 30.2W at 24/0900 UTC or 70 nm W of Faial Island In The Central Azores moving WSW at 8 kt. Estimated minimum central pressure is 999 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Seas are peaking near 22 ft near the center. Gaston has now turned WSW, and this continued motion should keep Gaston moving through the western Azores today. Swells generated by Gaston are expected to affect portions of the Azores today, prolonging life-threatening surf and rip current conditions.

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 near 20.2N 20.8W at 24/0900 UTC or 310 nm NE of the Cabo Verde Islands moving N at 9 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Seas are peaking at 12 ft near and N of the center. Numerous moderate convection is seen from 19N to 25N between the Western Sahara-Mauritania coast and 20W. A northward motion will continue through tonight before a turn toward the NE 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 near 14.7N 73.5W at 24/0900 UTC or 270 nm SE of Kingston Jamaica moving W at 12 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 13N to 16N between 72W and 77W. 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. Swells generated by Ian will impact Jamaica, the Cayman Islands, and Cuba over the next several days, causing life- threatening surf and rip current conditions. 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 15N22W through a 1009 mb low centered near 12N37W to 09N48W. An ITCZ then continues from 09N48W to southeast of Barbados at 11N55W. Scattered moderate convection extends along the entire length of the monsoon trough and ITCZ, from 04N to 13N. , 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 cold front has stalled early this morning, and now stretches from near Fort Myers, Florida to SE Louisiana. Scattered moderate convection is noted within about 30 nm of this boundary. Convection previously associated with a low pressure trough in the eastern Bay of Campeche has diminished early this morning. Moderate to fresh ENE winds and seas of 3 to 4 ft are evident offshore from the Florida Big Bend area. Mainly gentle ENE to ESE winds with 1 to 3 ft seas prevail for the rest of the Gulf.

For the forecast, Tropical Storm Ian will move to 14.6N 75.2W this afternoon, 15.2N 77.4W Sun morning, and 16.5N 79.4W Sun afternoon. Tropical Storm Ian will strengthen to a hurricane near 18.2N 81.0W Mon morning, reach 20.2N 82.4W Mon afternoon, and 22.0N 83.3W Tue morning. Hurricane Ian will change little in intensity as it moves through the southeastern Gulf of Mexico early Wed. Conditions will likely begin to deteriorate across the eastern Gulf of Mexico by early next week.

Caribbean Sea

Please refer to the Special Features section above on Tropical Storm Ian moving across the basin.

Aside from convection in association with Tropical Storm Ian, activity across the basin has diminished early this morning. Mainly moderate E to SE winds and seas of 4 to 7 ft dominate the central and eastern basin. Light to gentle winds and seas of 1 to 3 ft prevail for the western basin.

For the forecast, Tropical Storm Ian will move to 14.7N 73.9W Sat morning, 15.1N 76.3W Sat evening, and 16.1N 78.4W Sun morning. Tropical Storm Ian will be at 17.6N 80.1W Sun evening, strengthen to a hurricane near 19.3N 81.5W Mon morning, and reach 21.2N 82.4W Mon evening. Hurricane Ian will change little in intensity as it moves to the southeast Gulf of Mexico late Tue. Deteriorating marine conditions can be expected near the track of Ian, including the central Caribbean tonight through early Sun, and portions of the northwest Caribbean later on Sun through Tue. Locally heavy rainfall and gusty winds will impact Jamaica and the Cayman Islands this weekend, in addition to portions of Hispaniola.

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 to the northwest Bahamas, where it becomes stationary and extends to near Boca Raton, Florida. Scattered moderate convection is noted within about 30 nm of this boundary. A band of convergence is also inducing scattered moderate convection from 31N59W to 24W65W. Refer to the Monsoon Trough/ITCZ section above for additional convection in the Atlantic Basin.

Ahead of the front, N of 27N and W of 51W, moderate SW winds prevail with seas of 9 to 13 ft in northerly swell. Behind the front, moderate to locally fresh NE to ENE winds and seas of 8 to 10 ft are noted. Near the Canary Islands, gentle to moderate NE to ENE trades and seas at 4 to 6 ft are present north of 26N between NW African coast and 35W. Outside the main influence of Tropical Storm Hermine, fresh NNE to NE winds with 8 to 10 ft seas exist from 22N to 26N between the Western Sahara- Mauritania coast and 23W. Moderate to fresh southerly winds with 6 to 8 ft seas are noted from 13N to 17N between the Senegal- Guinea Bissau coast and 22W. Otherwise, the Atlantic ridge is supporting gentle to locally moderate ENE to E winds and 4 to 7 ft seas north of 11N between 23W/35W and the Bahamas/Lesser Antilles. Light to gentle winds and 4 to 5 ft prevail for the rest of the Atlantic Basin.

For the forecast W of 55W, swell generated by Post-Tropical Cyclone Fiona continues to propagate southward to around 25N and as far E as 55W. Tropical Storm Ian is near 14.7N 73.5W 1003 mb at 5 AM EDT moving W at 12 kt. Maximum sustained winds are 40 kt with gusts to 50 kt. Ian will move to 14.6N 75.2W this afternoon, 15.2N 77.4W Sun morning, and 16.5N 79.4W Sun afternoon. Tropical Storm Ian will strengthen to a hurricane near 18.2N 81.0W Mon morning, reach 20.2N 82.4W Mon afternoon, and 22.0N 83.3W Tue morning. Hurricane Ian will change little in intensity as it moves through the southeastern Gulf of Mexico early Wed. Impacts from Ian may affect areas offshore Florida early next week.

Posted 4 hours ago by NHC Forecaster Konarik