[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 221048
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Thu Sep 22 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 0600 UTC surface analysis and satellite imagery through
1040 UTC.

...SPECIAL FEATURES...

Major Hurricane Fiona is centered near 27.4N 70.6W at 22/0900 UTC or
420 nm SW of Bermuda moving NNE at 11 kt. Estimated minimum
central pressure is 934 mb. Maximum sustained wind speed is 115
kt with gusts to 140 kt. Numerous moderate isolated strong
convection is from 25N to 33N between 63W and 73W. Peak seas near
Fiona are currently estimated to be 51 ft. On the forecast track,
the center of Fiona will pass just to the west of Bermuda
tonight, approach Nova Scotia on Friday, and move across Nova
Scotia and into the Gulf of St. Lawrence on Saturday. Little
change in strength is expected through tonight. Some weakening is
expected to begin on Friday, but Fiona is forecast to still be
producing hurricane-force winds Friday night and Saturday after it
has become post-tropical. 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 40.3N 35.4W at 22/0900
UTC or 330 nm WNW of Faial Island In The Central Azores moving
ENE at 15 kt. Estimated minimum central pressure is 999 mb.
Maximum sustained wind speed is 55 kt with gusts to 65 kt.
Scattered moderate and isolated strong convection is from 39N to
46N between 27W and 38W. On the forecast track, the center of
Gaston will move near or over portions of the Azores on Friday.
Gradual weakening is expected over the next few days. Please read
the latest NHC Forecast/Advisory and Public Advisory at
www.hurricanes.gov for more details.

A tropical wave is in the SE Caribbean with axis near 64W S of 17N,
moving W at 15 kt. Scattered moderate convection is S of 15N
between 59W and 69W. The disturbance is forecast to move west-
northwestward across the eastern Caribbean Sea during the next day
or two, and be over the central Caribbean Sea this weekend.
Regardless of development, locally heavy rainfall and gusty winds
are likely to affect the Windward Islands this morning. These
impacts are likely to spread to northern Venezuela, northeastern
Colombia, and the ABC island chain during the next couple of days.
There is a high chance of tropical cyclone formation during the
next 48 hours. Please refer to the latest Atlantic Tropical
Weather Outlook at hurricanes.gov for more details.

A tropical wave coming off the west coast of Africa extends from
05N to 20N with axis near 16W, moving W at 10 kt. Scattered
moderate convection is from 10N to 16N between 14W and 20W. The
tropical wave is forecast to move over the far eastern Atlantic
waters later today. Thereafter, environmental conditions are
forecast to be conducive for some development, and a tropical
depression could form by this weekend while the system moves
slowly northward, between west Africa and the Cabo Verde Islands.
The chance of tropical cyclone formation during the next 48 hours
is medium.

...TROPICAL WAVES...

Please see the Special Features section above for a full
description of the two tropical waves in the basin currently.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from 14N17W to 10N22W to a 1010 mb low
near 10N33W to 09N37W. The ITCZ begins near 09N38W to 10N56W.
Aside from the convection associated with the E Atlantic tropical
wave, scattered moderate convection associated with a 1010 mb low
is from 10N to 15N between 30W and 37W.

GULF OF MEXICO...

High pressure prevails over the Gulf coast states. Gentle to
locally moderate N to NE winds prevail over the northern half and
far SW gulf, with light to gentle winds elsewhere. Seas are in
the 2-4 ft range basin-wide.

For the forecast, a relatively weak pressure gradient across the
region will support mainly light to gentle variable winds through
Mon morning with locally moderate winds during this period. A
tropical wave, currently over the eastern Caribbean along 64W, is
likely to develop into a tropical cyclone while over the Caribbean
Sea, then approach the Yucatan Channel late Mon before moving
into the Gulf of Mexico by the middle of next week. In advance of
this system, moderate to fresh NE winds will develop over the
southern half of the basin by Mon afternoon.

CARIBBEAN SEA...

Please see the Special Features section above for details on a
strong tropical wave over the SE Caribbean Sea which has a high
chance of developing into a tropical cyclone within the next 48
hours. Otherwise, light to gentle variable winds are across the
remainder of the basin, west of 68W with 1-3 ft seas.

For the forecast, the tropical wave along 64W is likely to
develop into a tropical cyclone by the time it reaches the central
or western Caribbean in the next couple of days. There is a
chance it could strengthen as it approaches the Yucatan Channel
late Mon. Therefore, increasing winds, seas and squalls can be
expected with this system as it moves farther west in the basin.

ATLANTIC OCEAN...

Please read the Special Features section above for information
about Major Hurricane Fiona.

High pressure ridging prevails over the remainder of the basin,
to the east of Fiona, which is supporting mainly moderate E winds
with seas to 6 ft, except between the Cape Verde Islands and W
Africa where a tighter pressure gradient continue to support fresh
to locally strong N to NE winds and seas to 8 ft.

For the forecast W of 55W, Hurricane Fiona will move to 29.3N
69.7W this afternoon, 32.5N 66.9W Fri morning, 37.4N 63.3W Fri
afternoon, and further N of the area near 34.8N 65.1W by Fri
morning. Swells generated by Fiona will continue to spread
westward across the SW Atlantic toward the NW Bahamas and the E
coast of the United States during the next couple of days. The
swells could cause life-threatening surf and rip current
conditions. A cold front will drop south over the north waters
early on Fri through Sat night followed by fresh northeast winds
and building seas. High pressure will build in behind the cold
front.

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