[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 221205
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
805 AM EDT Wed Aug 22 2018

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 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based 0600 UTC surface analysis and satellite imagery through
1145 UTC.

...TROPICAL WAVES...

A far eastern Atlantic tropical wave has its axis along 24W/25W
from 05N-20N, moving westward at 10-15 kt. The wave is embedded
within a very dry and stable environment inhibiting convection at
this time.

A central Atlantic tropical wave has its axis extending along 44W
from 05N-19N, moving westward at 10-15 kt. This wave is also
embedded within a very dry and stable environment caused by
Saharan Air Layer outbreak migrating westward across the central
and eastern Atlantic. Isolated showers and thunderstorms are
within 120 nm either side of the wave from 09N to 11N.

An eastern Caribbean Sea tropical wave has its axis along 64W
from 07N-19N, moving westward near 10-15 kt. Scattered showers
and isolated thunderstorms are east of the wave from 11N to 13N.

A central Caribbean tropical wave has its axis along 74W/75W from
09N to 20N, moving westward near 15 kt. Scattered moderate
convection is between eastern Cuba and Jamaica, and over some
sections of northern Colombia.

The tropical wave that move inland the Yucatan Peninsula yesterday
is approaching 92W, with its northern extent reaching near 20N. It
is moving westward near 15 kt. Previous numerous showers and
thunderstorms observed over the western Yucatan Peninsula have
diminished to isolated showers and thunderstorms.

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends from the African coast near
17N16W to 11N24W to 10N34W to 06N42W. The ITCZ axis begins at
06N45W to 08N53W to 09N61W. Scattered moderate convection is
within 180 nm north of the ITCZ axis between 46W and 53W. Isolated
moderate convection is within 120 nm north of the monsoon trough
axis between 29W and 34W.

...DISCUSSION...

GULF OF MEXICO...

Weak ridging extends across the northern Gulf of Mexico along
26N anchored by a 1019 mb high centered near 26N92W. This is
maintaining light to gentle breezes and 1 to 3 ft seas. Gentle to
moderate easterly flow is noted elsewhere south of the ridge.
Scattered showers and thunderstorms are observed over the far
southwest section of the gulf south of 21N and west of 94W in
association with a trough that moved offshore the Yucatan
Peninsula during the overnight hours. This activity is expected
to remain active during the morning before weakening during
the afternoon. It should then reform tonight and Thu night
as the surface trough again moves across those same waters.
Relatively weak high pressure ridging will remain across the
northern gulf waters, with the associated gradient producing
gentle to moderate anticyclonic flow through Fri.

CARIBBEAN SEA...

Two tropical waves are moving across the basin. Refer to the
section above for details. An upper level trough extends across
the west Caribbean enhancing convection across Cuba and adjacent
waters north of 18N and west of 75W. The pressure gradient across
the area will maintain fresh to strong winds over the south
central Caribbean off the coast of Colombia and across the Gulf of
Venezuela through Thursday. Moderate to fresh trades will
continue elsewhere through this period also. Little change is
expected with the present synoptic set-up through Fri.

ATLANTIC OCEAN...

Over the western Atlantic, a surface trough is analyzed from near
28N78W to 25N79W. Isolated showers and thunderstorms are noted
near this trough affecting the northern Bahamas. Two tropical
waves are moving across the basin. Refer to the section above for
details. Another trough extends along 51W from 21N to 30N. No deep
convection is noted with this trough. A 1025 mb high center is
analyzed north of 31N and extends a ridge across the remainder of
the basin. The trough extending across the central Bahamas will
continue westward during today. Another trough extends from 28N61W
to 21N67W. Scattered showers and thunderstorms are seen from 24N
to 28N between 62W and 70W. Expect foe this activity to continue
through tonight. Saharan dust and associated dry air, as also
mentioned above under Tropical Waves, is noted mainly east of
about 60W on GOES-16 Saharan Air Layer animation is inhibiting
convection from developing across the eastern and central Atlantic
waters.

For additional information please visit
http://www.hurricanes.gov/marine

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