Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Fri Sep 30 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... Hurricane Ian is centered near 33.2N 79.1W at 30/1800 UTC or 48 nm ENE of Charleston, South Carolina moving N at 13 kt. Estimated minimum central pressure is 977 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. Seas 12 ft or higher extend over the forecast waters up to 270SE and 180SW quadrants. All convection is north of the discussion waters. Ian is forecast to turn toward the north-northwest by tonight and will move inland across eastern South Carolina and central North Carolina tonight and Saturday. Swells generated by Ian and a nearby frontal system are affecting the east coast of Florida, Georgia, the Carolinas, and the northwestern Bahamas. These swells are likely to cause life- threatening surf and rip current conditions. Please consult products from your local weather office. Swells will subside along the northern coast of Cuba and the northeastern coast of the Yucatan peninsula today. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT4.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT4.shtml for more details. East Atlantic Gale Warning: Meteo-France has issued a Gale Warning for the Agadir and Tarfaya Zones in the East Atlantic. North winds of 34-40 kt (Force 8) with gusts are expected through 01/0300 UTC. Seas are 8-11 ft in N swell. For more information, please see the latest High Seas Forecast issued by Meteo-France at http://weather.gmdss.org/II.html ...TROPICAL WAVES... An eastern Atlantic tropical wave extends along 22W, from 17N southward, moving W at 10 to 15 kt. Scattered showers isolated moderate convection is in the vicinity of the wave axis and the Monsoon Trough. This tropical wave has a LOW (10%) chance of development through 48 hours and a MEDIUM (60%) chance of development through five days. A central Atlantic tropical wave extends is along 37W, from 19N southward, moving W at 10-15 kt. Scattered moderate convection is from 09N to 12N between 34W and 37W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Mauritania near 17N16W to 07N25W to 07N38W. The Monsoon Trough resumes from 10N41W to 08N48W. The ITCZ continues from 08N48W to 09N60W. Convection is isolated and weak along these boundaries. GULF OF MEXICO... Moderate to fresh N to NW flow in the lee of Hurricane Ian continues across the basin, with subsiding seas of 4-6 ft. For the forecast, cool, dry conditions will accompany the gentle to moderate N winds across the Gulf of Mexico today. Fresh to strong NW winds occurring in the SW Gulf will diminish by tomorrow morning. Winds should then remain tranquil for the next several days over the Gulf. CARIBBEAN SEA... An upper-level trough over the east-central Caribbean is supporting scattered showers and tstorms in the E Caribbean. Elsewhere, a weak pressure gradient in the lee of Hurricane Ian supports light to gentle trades and 2-4 ft seas across the basin. The exception is the far NW Caribbean, where NE winds are locally fresh and 4-6 ft N swell propagating out of the Gulf of Mexico continues. A surface trough is analyzed in the NW Caribbean from the south coast of Cuba near 21N78W to 16N82W. For the forecast, a surface trough is forecast to persist over the NW Caribbean through Mon. Moderate to fresh NW to N winds are expected west of the trough through tonight. Elsewhere, gentle to moderate E to SE trades and slight to moderate seas will persist across the basin. ATLANTIC OCEAN... For details on Hurricane Ian and impacted waters please refer to the SPECIAL FEATURES section above. Please also see the SPECIAL FEATURES section for information on the East Atlantic Gale Warning. In NW sections of the Discussion Waters, the extent of 20 kt or greater SE to S winds associated with the circulation of Hurricane Ian are occurring north of 26N and west of 70W. Seas greater than 8 ft are NW of a line from 31N72W to 27N80W. An early season cold front, formed by the broad circulation in the lee of Hurricane Ian, enters the waters near 31N75W and continues to the north coast of Cuba near 23N82W. The analyst was quite pleased with the cool and dry conditions in Miami this morning. In the East Atlantic near the Cabo Verde Islands, fresh to strong NE winds were detected by the latest scatterometer pass within an area from 17N to 21N between 21W and 28W. Seas are 6-8 ft in this area of fresh to strong winds. Elsewhere, gentle to moderate anticyclonic flow prevails across the basin with 4-6 ft seas. For the forecast west of 55W, Hurricane Ian north of the area near 33.2N 79.1W 977 mb at 02 PM EDT moving N at 13 kt. Maximum sustained winds 75 kt gusts 90 kt. Ian will continue moving toward the north away from our waters today, and winds and seas should diminish north of the Bahamas by tomorrow afternoon. An early season cold front has formed east of Florida in the wake of Ian. This front should weaken, but be reinforced by another cold front moving off of the coast of NE Florida on Sun. The combined cold front should reach from near 31N70W to 25N75W by Mon morning and dissipate by Tue.