[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 151055
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Wed Mar 15 2023

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
1010 UTC.

...SPECIAL FEATURES...

Atlantic Gale Warning: A cold front extending from SE of Bermuda
to across the Central Bahamas to NW Cuba will continue moving SE,
reaching 31N57W to central Cuba this evening, from near 30N55W to
the Windward Passage Thu morning, and from 20N55W through the
Leeward Islands by Fri morning. Strong to gale-force northerly
winds will occur in a narrow band immediately behind the front
as it moves through the Central and SE Bahamas tonight, and then
shifts across the SE waters and into the Caribbean Islands Thu
and Thu night. Large N swell will accompany this front, with seas
of 12 ft or greater spreading as far S as 22N and E of 73W Thu
night and Fri, with 12 ft seas then shifting E and gradually
subsiding through Sat night.

Atlantic Significant Swell Event: Large NW swell, producing
significant wave heights of 12 to 15 ft based on recent altimeter
data, prevails across the waters N of 27N between 35W and 48W.
This swell has been generated by deep low pressure moving across
the NE Atlantic and an associated frontal boundary sweeping
through the region, with the cold front currently extending from
31N30W to 25N40W. Mainly moderate winds are on both sides of the
front, generally north of 26N between 28W and 40W. Seas are
forecast to subside below 12 ft across these forecast waters by
late this afternoon.

Please read the latest High Seas Forecast at
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details on
these events.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic through the coast of Africa
near 09N13W then continues SW to near 04.5N20W. The ITCZ extends
from 04.5N20W to 01N34W to the Amazon Basin near 00N51W.
Scattered to numerous strong convection is noted from 02.5N to
07N between the African coast and 24W. Scattered moderate to
strong convection is noted from 04N to 04S between 22W and 47W.

GULF OF MEXICO...

A stationary front extends across the basin from NW Cuba to N of
the Yucatan Peninsula, then become ill defined westward to the
coast of Mexico. High pressure across the Tennessee Valley dominates
the remainder of the Gulf waters N of the front and the State of
Florida. An upper level disturbance moved across the south
central Gulf and the Yucatan Peninsula overnight, triggering
scattered showers and thunderstorms near the front in this region.
Overnight scatterometer data showed NE winds to near gale-force
off the NW coast of the Yucatan, and later altimeter data measured
seas 8 to 10 ft there. Associated weather has since shifted into
the Gulf of Honduras, and wind and seas are gradually diminishing
in the SW Gulf. Currently, fresh to locally strong NE to E winds
are noted N of the front, with seas of 7 to 9 ft over the western
Gulf, and 4 to 7 ft over the eastern Gulf.

For the forecast, the stationary front will be reinforced with a
surge of fresh to strong NE winds, pushing the front SE of the
basin this afternoon. Return flow will develop across the W Gulf
by Wed night, become fresh to strong early Thu and spread to the
entire Gulf Thu night, ahead of the next cold front. This next
front will move into the NW Gulf Fri morning, reaching from
Apalachee Bay, Florida to the central Bay of Campeche Sat morning.
Brief gale-force N winds are expected behind the front offshore
of the upper Mexican waters late Fri afternoon, shifting to
offshore Veracruz Fri evening and night.

CARIBBEAN SEA...

A weak high pressure ridge prevails N of the basin along 22N,
ahead of the approaching cold front in the Gulf of Mexico. This
is resulting in light to gentle winds over the NE Caribbean,
including Puerto Rico and regional waters. Fresh to locally strong
trades are within about 120 nm of the coast of Colombia and
Venezuela. Gentle to moderate wind prevail elsewhere, except in
the lee of Cuba where light and variable winds are observed. Seas
are in the 4 to 7 ft range in the south-central Caribbean, 3 to 5
ft across the eastern Caribbean, and 2 to 4 ft elsewhere.

A 90 nm wide band of strong thunderstorms has shifted SE across
the Gulf of Honduras in recent hours, associated with an upper
level disturbance. Elsewhere, patches of low level clouds, with
isolated to scattered moderate convection is seen across the NW
Caribbean.

For the forecast, the ridge north of the area will shift NE
through the rest of the week as a cold front sinks slowly S-SE
across the northwestern basin this afternoon and evening, reaching
from the Windward Passage to Belize on Thu, and then from the
northern Leeward Islands to the central Caribbean along 17N Fri.
Strong winds will follow the front, locally higher in Atlantic
passages, with large N swell spreading through Atlantic passages
early Fri through Sat. Another front is expected to stall near or
just N of the Yucatan Channel on Sun.

ATLANTIC OCEAN...

A cold front extends from 31N58W across the Central Bahamas to
NW Cuba. Currently, seas of 8 to 10 ft are noted per altimeter
data behind the front and E of the Bahamas. Moderate to fresh N
winds are N of 26N between 75W and the E coast of Florida, while
strong NW winds are elsewhere behind the front and N of 28N. Gale
force winds are expected to develop in a narrow band immediately
behind this front tonight into Thu morning. Please, see the
Special Features section above for more details.

A second cold front stretches from 31N30W to 25N38W where it
becomes stationary to 23N57W. Large NW swell, with seas in excess
of 12 ft, follows the front. Please, see the Special Features
section above for more information.

A 1020 mb high pressure is located between the fronts near
27N48W. Another high pressure center of 1023 mb is NE of the
Madeira Islands. Fresh to strong NE winds and seas of 7 to 8 ft
are noted between the coast of Western Saharan and the Canary
Islands. Mainly moderate NE trades are blowing across the
tropical Atlantic with seas of 7 to 10 ft in Nw to N swell
prevailing E of the Lesser Antilles.

For the forecast W of 55W, the cold front across the western
Atlantic will move SE and reach from 31N57W to central Cuba this
evening, from near 30N55W to the Windward Passage Thu morning, and
from 20N55W through the Leeward Islands by Fri morning. Strong to
gale-force northerly winds immediately behind the front will move
through the Central and SE Bahamas Wed night, and then shift
across the SE waters and into the Caribbean Islands Thu and Thu
night. Large N swell will accompany this front, with seas of 12 ft
or greater N of 22N and E of 73W. Yet another cold front is
expected to move off NE Florida late Sat, with fresh to strong
southerly winds ahead of it Fri evening through Sat. That front is
expected to reach from 31N70W to S Florida late Sun before
stalling.

$$
Stripling
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