[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 291655
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Thu Sep 29 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
1640 UTC.

...SPECIAL FEATURES...

Tropical Storm Ian is centered near 28.7N 80.4W at 29/1500 UTC or
20 nm NNE of Cape Canaveral, Florida moving NNE at 8 kt.
Estimated minimum central pressure is 987 mb. Maximum sustained
wind speed is 60 kt with gusts to 75 kt. Tropical storm force
winds extend outward up to 360 nm from the center in the NE
quadrant, 200 nm NW quadrant, 120 nm SE quadrant and 150 nm SW
quadrant. Peak seas over Atlantic waters offshore north Florida
are 21 ft. Peak seas over the eastern Gulf of Mexico have subsided
now to 11 ft. Scattered to numerous moderate and isolated strong
convection extends outward from the center 450 nm in the E
semicircle and 240 nm NW quadrant, including over portions of
northeastern Florida. A band of thunderstorms about 60 nm wide
extends to the southeast of Ian along 76.5W from 22N-28N,
including over portions of the central and northwest Bahamas. On
the forecast track, Ian will approach the coast of South Carolina
on Friday. Ian is expected to become a hurricane again this
evening and make landfall as a hurricane on Friday.

Tropical Depression Eleven is centered near 19.1N 37.4W at
29/1500 UTC or 785 nm WNW of the Cabo Verde Islands moving NW at
12 kt. Estimated minimum central pressure is 1008 mb. Maximum
sustained wind speed is 30 kt with gusts to 40 kt. Peak seas are
near 9 ft. Scattered moderate to strong convection is occurring
within 240 nm of the center in the NE quadrant. A northwestward
motion is expected until the depression dissipates in the next day
or so.

Please read the latest High Seas Forecast issued by the National
Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml
and the latest NHC Forecast/Advisory and Public Advisory at
www.hurricanes.gov for more details on both tropical cyclones.

...TROPICAL WAVES...

An Atlantic Ocean tropical wave axis extends along 30/31W from
07N to 20N, moving W at 10-15 kt. Scattered moderate isolated
strong convection is occurring within 90 nm either side of the
wave axis from 12.5N to 16N.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of southern Mauritania
near 17N16W to 15N20W to 08N28W to 08N34W. The monsoon trough
resumes from 10N37W to 10N45W. The ITCZ extends from 10N45W to
09N50W to 11N57W. Aside from the convection mentioned above,
scattered to numerous moderate convection is noted from 02N-10N
between 11W-22W.

GULF OF MEXICO...

Tropical Storm Ian is centered 20 nm offshore of Cape Canaveral,
FL, over the Atlantic. As of 1500 UTC, the tropical storm warning
has been discontinued for the Gulf Coast of Florida. However,
strong to near-gale force N winds are still occurring east of 85W
and north of 26N. Of note, a 1022 mb high pressure is centered
over NE Mexico near 26N100W. Moderate to fresh N winds are
prevalent elsewhere across the Gulf of Mexico, west of 85W, due to
the strong pressure gradient between the high pressure and Ian.
The exception is near the coast of Veracruz, where strong NW to N
winds are likely occurring. Seas of 8-11 ft cover the E Gulf, east
of 88W from the Yucatan Channel to 29N. Seas of 7-9 ft cover the W
Gulf, west of 88W.

For the forecast, winds and seas are forecast to gradually
diminish over the Gulf waters over the next couple of days. By
sunrise Friday, winds over the E Gulf will diminish to fresh and
seas will subside to less than 8 ft. Looking ahead, a cold front
may enter the northeast Gulf late Sat or Sun then stall and
dissipate.

CARIBBEAN SEA...

A sharp upper-level trough with an axis from Puerto Rico to the N
coast of Colombia is generating numerous moderate and scattered
strong convection across the eastern Caribbean, east of 67W,
extending to 55W, including near the Windward and southern Leeward
Islands. In the SW Caribbean, the east Pacific monsoon trough is
inducing scattered moderate and isolated strong convection mainly
south of 12N between 74W-80W, including along the coast of NW
Colombia. A surface trough extends across the NW Caribbean from
22N81W to 17N86W to northern Guatemala. Scattered moderate showers
prevail within 60 nm of the trough axis.

The latest ASCAT satellite wind data indicates that mostly gentle
wind speeds prevail across the basin. Moderate NW to N winds are
occurring over the far NW Caribbean, to the west of the
aforementioned surface trough. Seas are 2-3 ft across the basin,
to the east of 83W. Over the NW Caribbean, west of 83W, seas are 3
to 7 ft, except 7 to 9 ft in the Yucatan Channel in N swell.

For the forecast, the large N swell will continue to spread
through the Yucatan Channel through tonight before subsiding.
Elsewhere, gentle to moderate winds and slight to moderate seas
will persist across the basin.

ATLANTIC OCEAN...

For details on Tropical Storm Ian, centered just offshore Cape
Canaveral, FL, please read the Special Features section above.
Winds of 20 kt or greater associated with the circulation of Ian
currently extend over the waters to the west of 73W and north of
25N. Seas of 8 ft or greater associated with Ian extend over the
waters west of 72W and north of 26N. Convection associated with
Ian is limited to areas mainly west of 73W.

An upper-level low near 22N65W extends a sharp upper-level trough
SW to Puerto Rico to the N coast of Colombia. Numerous moderate
and scattered strong convection prevails from 09N-18N between
55W-67W. Associated scattered moderate convection is also seen
from 18N-25N between 60W-70W. Farther east, an upper-level low
centered near 31N42W is inducing scattered moderate convection
mainly north of 30N between 33W-42W. Aside from areas near Ian
and T.D. Eleven, gentle to moderate trades prevail across the
basin with 4-7 ft seas. One exception is off the coasts of Morocco
and Western Sahara, where fresh to strong N to NE winds and 6-8
ft seas prevail.

For the forecast west of 55W, Tropical Storm Ian is forecast to
strengthen to a 65 kt hurricane near 30N80W this evening, move N
of the area to near 32N80W Fri morning, then move inland and
weaken to a tropical storm near 34N 80.3W Fri evening. Winds will
diminish to below 25 kt over the forecast waters by Sat morning,
and seas will subside to below 8 ft by late Sat afternoon.

$$
Hagen
This weather bulletin was brought to you by:
www.nashvilleweather.net