[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 011728
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
128 PM EDT Sun Jul 1 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 on 1200 UTC surface analysis and satellite imagery through
1545 UTC.

...TROPICAL WAVES...

The tropical wave that most recently emerged off the west coast
of Africa has an axis extending from 03N23W to 16N23W and is
moving W at around 20 kt. Scattered moderate and isolated strong
convection is noted from 05N to 12N between 20W and 29W. A total
precipitable water surge coincides with this wave.

A tropical wave has an axis extending from 03N44W to 18N44W. This
wave is quickly moving W at around 30 kt. This wave is well
defined in model 700 and 850 mb fields and coincides with an
inverted-V signature in total precipitable water data. This wave
is surrounded by Saharan dust which is inhibiting deep
convection.

A tropical wave has an axis extending from 04N60W to 20N59W,
moving westward at 15 to 20 knots. This wave is clearly defined
with an inverted-V signature evident in visible satellite
imagery. Scattered moderate convection is from 07N to 15N between
54W and 70W. Saharan dust surrounds the northern portion of this
wave. Tropical moisture associated with this feature will continue
to spread west over the southeast and south-central Caribbean,
well ahead of the actual wave axis.

A tropical wave has an axis extending N from central America to
the Gulf of Honduras to 19N85W, as depicted in the 1500 UTC
analysis. Infrared and visible satellite imagery as well as total
precipitable water data confirm the location of this wave. The
wave will continue across central America tonight, enhancing
shower and thunderstorm activity.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic Ocean from the coast of
Senegal near 14N16W and extends to 09N22W to 06N30W. The ITCZ
extends from 06N30W to 05N43W, then resumes west of a tropical
wave near 05N47W to 08N58W. Aside from the convection associated
with the tropical waves, scattered moderate convection is observed
from 06N to 10N E of 20W, and within 90 nm of the monsoon trough
and ITCZ axis.

...DISCUSSION...

GULF OF MEXICO...

A surface trough extends over the northeastern Gulf from a 1016 mb
low near 30N85W to 29N86W to 28N89W. Abundant cloudiness and
numerous showers and thunderstorms are associated with the
low/trough affecting mainly the waters N of 27N and E of 89W. The
low is dissipating today, and the trough will drift northwestward
through tonight. Scattered showers and thunderstorms will
continue over much of the NE and north- central Gulf waters
through at least Mon associated with this system.

The remainder of the basin is under the influence of a weak high
pressure center of 1016 mb located over the north-central Gulf
near 28N90W. This system is producing light to gentle
anticyclonic flow and seas of 1-3 ft over the eastern half of the
Gulf, and gentle to moderate SE to S winds and seas of 3-5 ft
over the western half of the Gulf. This weak high pressure pattern
will change little through mid-week. A surface trough will emerge
off the Yucatan Peninsula each evening through Wed, enhancing
nocturnal winds over the SW Gulf through this period.

CARIBBEAN SEA...

A tropical wave is moving across the western Caribbean and
central America. Please see the Tropical Waves section for
details. Morning scatterometer data depicted fresh to strong winds
across the south-central Caribbean south of 14N between 70W and 78W,
while moderate to fresh trades prevail across the remainder of
the basin S of 18N and E of 82W. Light to gentle winds are noted
over the NW Caribbean. A surface ridge will remain north and
northeast of the Caribbean and Tropical N Atlantic waters through
the next few days. Fresh to strong winds across the south-central
Caribbean will gradually diminish through Tue before strengthening
again on Wed.

Convection continues to flare up over the SW Caribbean mainly in
the vicinity of the monsoon trough, which is just north of Panama.
An upper-level low, currently just south of central Cuba, will
drift westward across the NW Caribbean through Mon, and will
enhance convection across the extreme western Caribbean waters
and over land areas across the NW Caribbean.

ATLANTIC OCEAN...

Three tropical waves are moving across the waters between the
coast of West Africa and the Lesser Antilles. Refer to the
Tropical Waves section above for details. A weak surface high
center of 1019 mb is located near 28N75W. A surface trough is just
E of this high, and extends from 32N64W to 26N67W. Numerous
showers and scattered thunderstorms are from 25N to 30N between
62W and 73W, and elsewhere within 90 nm of the trough axis. The
high will weaken as this trough moves westward across the NW
Bahamas Tue, and inland Florida Wed. Enhanced shower and
thunderstorm activity is expected to continue in the vicinity of
the trough.

Another surface trough is over the central Atlantic and extends
from 32N51W to 26N52W. Light winds are on either side of the
trough axis based on scatterometer data from this morning. This
trough is a surface reflection of an upper-level low spinning near
29N52W. Scattered showers and thunderstorms are associated with
this system from 27N to 32N between 45W and 54W. Surface high
pressure located NW of the Azores is in control of the remainder
of the central and eastern Atlantic discussion waters.

GOES-16 RGB Geocolor imagery continues to show an extensive area
of African dust that extends from the west coast of Africa to the
eastern Caribbean this morning. The Saharan dust occasionally
obscures sky conditions near the Caribbean islands. The dust turns
skies hazy, reducing visibility and can result in poor air
quality.

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

$$
Latto
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