AXNT20 KNHC 301202 AAA

Tropical Weather Discussion...UPDATED
NWS National Hurricane Center Miami FL
1205 UTC Fri Sep 30 2022

Updated with the 1200 UTC Intermediate Advisory for Hurricane Ian AND to add the East Atlantic Gale Warning Special Feature

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 0945 UTC.


Hurricane Ian is centered near 31.4N 79.1W at 30/1200 UTC or 91 nm SSE of Charleston South Carolina moving N at 8 kt. Estimated minimum central pressure is 984 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. 12 ft seas or higher extend over the forecast waters up to 180SE and 120SW quadrants. Numerous moderate to strong convection prevails N of 30N between 75W-81W. A feeding band has developed with scattered moderate convection extending along 76W and N of 22N. On the forecast track, the center of Ian will approach and reach the coast of South Carolina today, and then move farther 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 8-9 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


An eastern Atlantic tropical wave extends along 19W, from 02N to 17N, moving W at 10 to 15 kt. Scattered moderate convection is observed from 05N to 11N, between the coast of Africa and 25W.

A central Atlantic tropical wave extends along 35W, from 07N to 20N, moving W at 10 kt. There is no significant convection associated with this wave.


The monsoon trough extends from the coast of Mauritania near 18N16W to 08N35W, then resumes near 10N41W to 09N47W. The ITCZ continues from 09N47W to 09N59W. Convection is isolated and weak along these boundaries.


The gradient between high pressure over northern Mexico and Hurricane Ian east of northern Florida is supporting moderate to fresh northerly flow across the basin. Seas are 6-8 ft on an abating trend.

For the forecast, the area of moderate to fresh northerly winds over the NE Gulf, mainly N of 28N and E of 88W, with seas reaching 8 ft will dissipate today. Fresh NW to N winds and seas of 8 ft are prevail over the SW Gulf, including the Veracruz area. Winds and seas are forecast to gradually diminish over the Gulf region this morning. Looking ahead, a cold front may enter the NE Gulf this weekend, then stall and dissipate across the area early next week.


An upper-level trough over the east-central Caribbean is supporting scattered moderate convection from 11N to 20N between 64W-75W. Otherwise, Hurricane Ian to the north is actually improving conditions by interrupting the usual pressure gradient. Winds are gentle to moderate across the basin with slight seas. The only exception is in the extreme NW basin, where 4-8 ft northerly swell is propagating through the Yucatan Channel from the Gulf of Mexico.

For the forecast, large N swell produced from Ian will continue to spread through the Yucatan Channel through this morning. A surface trough is forecast to persist over the NW Caribbean through at least Sun. Moderate to fresh N winds are expected W of the trough through tonight. Elsewhere, gentle to moderate winds and slight to moderate seas will persist across the basin.


For details on Hurricane Ian and the tropical waves across the basin, please refer to the sections above.

Winds of 20 kt or greater associated with the circulation of Ian currently extend over the waters to the west of 72W and north of 26N. Seas of 8 ft or greater associated with Ian extend over the waters west of 72W and north of 27N.

In the central Atlantic, winds are mainly gentle to moderate from the east with 4 to 6 ft seas. The only exception is a small area of decreasing fresh winds and abating 6-8 ft seas in the vicinity of Post-Tropical Depression Eleven near 20N37W. In the eastern Atlantic, a tighter pressure gradient is supporting moderate to fresh NE winds with 6-8 ft seas.

For the forecast west of 55W, Hurricane Ian near 31.4N 79.1W 984 mb at 8 AM EDT, moving N at 8 kt. Maximum sustained winds 75 kt gusts 90 kt. Ian will move to 32.5N 79.3W this afternoon, move inland and weaken to a tropical storm near 34.6N 79.9W Sat morning, weaken as an extratropical cyclone near 36.3N 80.3W Sat afternoon, and dissipate Sun morning.

$$ ERA/Mahoney