[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 300335
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0605 UTC Fri Apr 30 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 0000 UTC surface analysis and satellite imagery through
0300 UTC.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Guinea-Bissau near
11N15W to 07N20W. The ITCZ continues from 07N20W to 03N25W to
04N40W to 02N50W. Scattered moderate and isolated strong
convection is noted from 00N-03N between 10W-16W. Scattered
moderate convection is evident from 02N-05N between 25W-28W.

GULF OF MEXICO...

A surface ridge extends from 1018 mb high pressure centered over
north central Florida westward across the northern Gulf coast
into central Louisiana. A weak stationary front is analyzed west
of the ridge, along the Texas coast. Persistent areas of smoke
were noted on earlier satellite imagery across much of the western
Gulf, west of 90W. This smoke is limiting visibility in some
areas, and originates from agricultural and forest fires over
southern Mexico. Platform observations are also showing areas of
fog in the northwest and north-central Gulf, with visibility
reported to be as low as one and a half miles in some areas in a
combination of fog and smoke. Moderate to fresh winds are active
off northern and western coast of Yucatan, where an evening
trough is setting up. Light and variable breezes are evident over
the far northeast Gulf, close to the high pressure. Gentle to
moderate E to SE winds are evident elsewhere. Seas are 5 to 7 ft
over the western Gulf, and 1 to 3 ft over the northeast Gulf, and
3 to 5 ft elsewhere.

For the forecast, a complex frontal system moving off the Texas
coast tonight will reach from northern Florida to the western Bay
of Campeche early Sat, then move northward as a warm front later
in the weekend. Scattered thunderstorms are possible near the
Texas coast Fri night and Sat. Areas of smoke and haze are
possible in the W Gulf from agricultural fires in southern Mexico.
Fresh southerly return flow will prevail early next week over
much of the basin.

CARIBBEAN SEA...

A sharp upper level trough extends from the central Atlantic,
across Hispaniola, and into the south-central Caribbean. Divergent
flow aloft on the southeast side of this trough is supporting a
few showers over the southeast Caribbean, moving into the Windward
Islands. Dry, subsident northerly flow aloft is evident elsewhere,
between the trough and an upper ridge centered over southern
Mexico. This is suppressing any showers or thunderstorms elsewhere
across the basin, except for localized thunderstorms in the
eastern Gulf of Gonave off Haiti. At the surface, trough is
analyzed over Yucatan and high pressure was centered east of the
Bahamas. An earlier scatterometer satellite pass indicated fresh
to strong E to SE winds from the just north of the Bay Islands of
Honduras to northern Belize. These winds are presumed to still be
active, between the high pressure and the trough over Yucatan.
Fresh NE winds are evident in the northern Windward Passage, but
generally moderate trade winds are noted elsewhere. Seas are 4 to
6 ft over the northwest Caribbean, west of 85W, and 3 to 5 ft
elsewhere.

For the forecast, fresh to strong east to southeast winds are
expected to continue to pulse in the Gulf of Honduras during the
next several nights. Gentle to moderate winds will continue
elsewhere across the basin through Sun, becoming moderate to fresh
across the eastern and central Caribbean early next week.

ATLANTIC OCEAN...

A broad surface ridge is analyzed north of 20N and west of 35W,
anchored by 1024 mb high pressure near 30N60W. An area of moderate
to fresh E winds are evident north of Hispaniola and near the
approaches to the Windward Passage. But elsewhere this pattern is
supporting gentle breezes north of 20N, except for moderate S to
SW winds off Florida, and moderate trades south of 20N. Seas are
generally 3 to 5 ft west of 35W. East of 35W, a trough reaches
from the Canary Islands to 23N35W. Moderate N to NE winds and 5 to
6 ft are evident north of this trough, with moderate NE winds and
3 to 5 ft seas south of this trough. An upper trough reaches from
the north central Atlantic through 30N55W to Haiti. Divergence
aloft east of this trough is supporting a few showers within 90 nm
to the southeast of this upper trough.

A 1024 mb high pressure centered near 31N60W supports moderate to
locally fresh trade winds across the waters south of 24N as well
as north of 24N and west of 77W, and gentle to moderate
anticyclonic winds north of 25N and west of 65W. Seas are in the
2-4 ft range north of 27N and west of 65W, and 4-7 ft south of 27N
and west of 65W. A trough extends from 31N49W to 25N60W. Isolated
showers are possible near the trough. To the east, an 1011 mb low
pressure area is centered near the Cabo Verde Islands with a
trailing trough reaching through 22N26W to 26N38W. Light and
variable winds dominate the waters north of 22N and east of 65W,
with moderate trades south of 22N and east of 65W. Seas are in the
4-6 ft range across the open waters of the tropical central and
eastern Atlantic.

For the forecast for the waters west of 65W, the next cold front
will enter the waters to the east of northern Florida Fri night
into early Sat, then weaken and shift east of the forecast area on
Sun. Moderate to fresh winds are expected in the vicinity of the
front. In the wake of the front, high pressure will persist east
of the area early next week, leading to moderate southerly winds
over the western Atlantic.

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