AXNT20 KNHC 251728
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Sun Sep 25 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
Tropical Storm Ian is centered near 15.2N 79.8W at 25/1800 UTC
or 300 nm SSE of Grand Cayman moving WNW at 10 kt. Estimated
minimum central pressure is 1001 mb. Maximum sustained wind
speed is 45 kt with gusts to 55 kt, and seas are peaking near 14
ft near in just N of the center. Numerous moderate to scattered
strong convection is noted from 10N to 21N between 75W and 85W.
On the forecast track, the center of Ian is forecast to pass
well southwest of Jamaica today, and pass near or west of the
Cayman Islands early Monday. Ian will then move near or over
western Cuba Monday night and early Tuesday and emerge over the
southeastern Gulf of Mexico on Tuesday. Rapid strengthening is
forecast to begin later today or tonight. Ian is expected to
become a hurricane tonight or early Monday and reach major
hurricane strength Monday night or early Tuesday before it
reaches western Cuba.
Ian is expected to produce heavy rainfall, flash flooding, and
possible mudslides in areas of higher terrain, particularly over
Jamaica and Cuba. Flash and urban flooding is possible across
the Florida Keys and the Florida peninsula through midweek.
Additional flooding on rivers across northern Florida and parts
of the southeast U.S. cannot be ruled out later this week.
Life-threatening storm surge and hurricane-force winds are
expected in portions of western Cuba beginning late Monday,
where a hurricane warning is now in effect. Efforts to protect
life and property should be rushed to completion. Regardless of
Ian's exact track and intensity, there is a risk of dangerous
storm surge, hurricane-force winds, and heavy rainfall along the
west coast of Florida and the Florida Panhandle by the middle of
the week. Residents in Florida should ensure they have their
hurricane plan in place, follow any advice given by local
officials, and closely monitor updates to the forecast.
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 39.4N 36.5W at 25/1500
UTC or 365 nm W of Faial Island In The Central Azores moving WNW
at 9 kt. Estimated minimum central pressure is 997 mb. Maximum
sustained wind speed is 45 kt with gusts to 55 kt, and seas are
peaking near 22 ft around the center. Gaston is expected to take
a gradual turn toward the west-southwest by tomorrow. Gradual
weakening is forecast over the next few days, and Gaston is
forecast to become a post-tropical cyclone by Monday. Swells
generated by Gaston are expected to affect portions of the Azores
today. These swells are likely to cause 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
There are no tropical waves present based on the latest analysis.
The monsoon trough extends off the coast of Western Sahara near
21N17W to a 1008 mb low near 23N20W to 10N25W to a 1009 mb low
near 14N36W to 08N41W. The ITCZ extends from 08N41W to 09N51W to
the coast of Guyana near 07N58W. Scattered moderate to isolated
strong convection is noted from 03N to 15N and E of 33W. Scattered
moderate convection is noted near the 1009 mb low from 12N to 16N
between 34W and 40W. Scattered moderate convection is north of
the ITCZ from 09N to 13N between 44W and 61W.
...GULF OF MEXICO...
Please refer to the Special Features section above on Tropical
Storm Ian, which is anticipated to impact the central eastern
Gulf by the middle of the week.
High pressure ridging is noted across the Gulf, with a 1014 mb
high near 28N94W in the NW Gulf. There are some scattered
thunderstorms noted in the SW Gulf near a trough extending along
the southern Mexico coast. Light to gentle winds are noted across
the entire basin with 1-2 ft seas.
For the forecast, conditions will begin to deteriorate across the
eastern and central Gulf of Mexico by Tue as Ian moves northward
from Cuba as a major hurricane. Residents along the Florida west
coast and Florida Panhandle need to monitor this system closely
and review your hurricane preparedness plan.
Please refer to the Special Features section above on Tropical
Storm Ian moving across the basin.
Outside the main impacts of T.S. Ian across the central
Caribbean, moderate to locally fresh E to SE winds with 3 to 6
ft seas are present across the eastern basin. Gentle to moderate
NNE to NE winds and seas at 2 to 4 ft exist over the
northwestern basin, while light to gentle winds and 1 to 3 ft
seas prevail for the southwestern basin.
For the forecast, Tropical Storm Ian is near 15.2N 79.8W 1001 mb
at 11 AM EDT moving WNW at 12 kt. Maximum sustained winds are 45
kt with gusts to 55 kt. Ian is expected to turn NW later today,
and intensify rapidly over the next 2-3 days. Ian will move to
near 16.5N 81.1W this evening as a hurricane, then reach near
18.1N 82.5W Mon morning, then move over western Cuba near 22N84.4W
Tue morning as a major hurricane, near 25.5N 84.8W Wed morning,
then continue northward Thu and inland across N Florida Fri
morning. Hazardous conditions will prevail in the NW Caribbean
through Tue, before winds and seas gradually subside as Ian moves
N of the basin.
Please refer to the Special Features section above for details on
Tropical Storm Gaston.
A stationary front extends from 31N58W to 27N69W and a weakening
front from 27N69W to 27N80W. Scattered moderate convection is
noted from 26N to 31N between 55W and 64W. Scattered
thunderstorms are near the tail-end of the dying boundary around
the northern Bahamas and off South Florida from 23N to 29N
between 75W and 80W. Moderate northeasterly winds are noted
north of the stationary front with light to gentle winds
elsewhere. Seas are around 4-6 ft in this area.
High pressure extends across the central Atlantic with light to
gentle winds. Seas are 7-10 ft, with the highest seas near 31N.
In the eastern Atlantic, moderate to fresh winds are noted off
the African coast, especially due to the influence of
post-tropical cyclone Hermine. Showers are noted across the
Canary Islands and off the coast of Morocco. Seas range from 5-9
For the forecast west of 55W, northerly swell from Fiona still
dominates the regional waters today and will decay below 8 ft to
the S of 27N tonight. Tropical Storm Ian is near 15.2N 79.8W
1001 mb at 11 AM EDT moving WNW at 12 kt. Maximum sustained
winds are 45 kt with gusts to 55 kt. Ian is expected to turn NW
later today, and intensify rapidly over the next 2-3 days. Ian
will move to near 16.5N 81.1W this evening as a hurricane, then
reach near 18.1N 82.5W Mon morning, then move over western Cuba
near 22N84.4W Tue morning as a major hurricane, reach near
25.5N84.8W Wed morning, then continue northward Thu and inland
across N Florida Fri morning. Strong southeasterly winds occurring
well to the E of Ian are expected to impact the waters W of 78W
as Ian moves through the Gulf of Mexico Tue afternoon through Fri