[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 262320
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Thu May 27 2021

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 1800 UTC surface analysis and satellite imagery through
2300 UTC.

...TROPICAL WAVES...

A tropical wave is analyzed along 14W S of 12N. Scattered moderate
and isolated strong convection is noted near the southern end of
the wave axis south of 05N between 13W to 17W. A surface trough
associated with the wave was noted in the scatterometer data. The
Hovmoller Diagram shows the westward propagation of the wave.

A second tropical is along 31N S of 11N, moving W around 15-20
kt. Scattered moderate convection is noted where the wave meets
the ITCZ. The wave has no significant surface component and is
analyzed based upon GFS-based 700 mb tropical wave diagnostics.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coast of Guinea Bissau
near 12N16W to 05N20W. ITCZ extends from 05N20W to 04N28W,
breaks for a tropical wave, then continues again from 04N33W to
04N52W along the coast of French Guiana. Scattered moderate and
isolated strong convection is noted south of 05N between 13W and
17W, from 02N to 05N between 17W and 28W, and within about 150 nm
N of the ITCZ.

GULF OF MEXICO...

A ridge dominates the Gulf waters producing mainly gentle to
moderate E to SE winds. Moderate easterly winds prevail across
the Straits of Florida. Seas are 1-3 ft over the NE Gulf and 3-5
ft elsewhere. Only a few showers are noted across the basin and
a band of high clouds extending across central Mexico into the
southern Gulf.

Gentle to moderate east to southeast winds are expected through
Sat night as weak high pressure off the NE Florida coast extends
westward to SE Texas and gradually weakens. Fresh northeast to
east winds will pulse nightly to strong off the Yucatan Peninsula
tonight through Sat. A cold front is expected to move across the
northern Gulf on Sat night into Sun and stall across the northern
Gulf Sun night. Expect moderate north to northeast winds behind
the front.

CARIBBEAN SEA...

A moderate pressure gradient between a 1025 mb high pressure
located off NE Florida and the Colombian low is contributing to
fresh to strong NE to E trades over the south-central Caribbean
based on latest satellite derived wind data. Elsewhere, moderate
to fresh trades prevail with the exception of gentle to moderate
winds in the NW Caribbean. Shallow moisture embedded in the trade
winds flow is noted across the area with some convective activity,
mainly due to local effects, across parts of the Greater Antilles.
Scattered showers and thunderstorms are occurring south of 12N
in the SW Caribbean associated with the Pacific monsoon trough
that extends from Costa Rica to northern Colombia. This convective
activity is affecting parts of Panama and Costa Rica. Seas are
7-10 ft in the S central Caribbean and 4-7 ft elsewhere.

Fresh to strong trades will prevail across the central portions
of the Caribbean through early Thu as high pressure resideS
offshore of the NE Florida coast. Winds will diminish significantly
Thu through early next week as the high collapses. Fresh winds
are expected to pulse to strong in the southern Gulf of Honduras
and the Windward Passage tonight.

ATLANTIC OCEAN...

Two tropical waves are moving westward across the tropical
Atlantic. Refer to the Tropical Waves section above for details.

Ridging from a 1030 mb Bermuda-Azores High centered at 38N45W
extends east-west north of our waters. A 1025 mb high pressure is
located just off NE Florida while another high pressure center
of 1025 mb is centered near 30N39W. A weak low pressure of 1022
mb is just E of Bermuda. A surface trough stretches from the low
center to 28N66W to 27N71W. This trough is associated with a
vigorous upper-level trough that extends southward across
Hispaniola into the Caribbean Sea. Scattered showers are near the
trough axis N of 28N. Moderate to fresh trades are noted roughly
S of 15N and W 30W, with an area of 20-25 kt winds N of the ITCZ
to about 12N between 45W and 50W where seas are 8 to 9 ft. Fresh
to strong northerly winds are from 18N to 24N between the W
coast of Africa and 20W. Seas are also in the 8 to 9 ft range
within this area of winds.

In the forecast for west of 65W, light winds will prevail north
of 24N through Thu as weak low pressure just east of Bermuda
interrupts the Atlantic ridge. Moderate to locally fresh winds
will continue across the Bahamas and Greater Antilles through
early Thu. Winds will become gentle to moderate Thu through Sun
as the Atlantic ridge extends from the east central Atlantic
weakly W-SW to Florida. Fri night, moderate to fresh southerly
winds will develop off the NE Florida coast ahead of a cold front
forecast to come off the southeastern CONUS early Sun. The cold
front will move across northern Florida on Sun before stalling
Sun night.

In the forecast for east of 65W, the Bermuda-Azores High will
weaken some on Thu leading toward a reduction in the NE to E
trades to moderate to fresh. Seas should diminish across the
waters below 8 ft by Fri.

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