[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 060006
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
806 PM EDT Sun Aug 5 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 1800 UTC surface analysis and satellite imagery through
2345 UTC.

...TROPICAL WAVES...

A tropical wave is in the E Atlc with axis extending from 08N-
18N along 27W, moving W at 10 kt. CIRA LPW imagery show abundant
shallow moisture in the wave environment. However, the wave is
being severely affected by Saharan dry air and dust, which is
limiting convection to isolated shower within 150 nm either side
of the wave axis.

A tropical wave is in the central Atlc with axis extending from
06N-20N along 37W, moving W at 15 kt. The wave continues to be
affected by intrusion of Saharan dry air and dust as indicated by
GOES-16 RGB and water vapor imagery at the lower levels. Shallow
moisture in the vicinity of the monsoon trough support scattered
moderate convection from 07N-11N between 31W-38W.

A tropical wave is in the E Caribbean with axis S of 20N along
67W, moving W at 10 kt. The wave is in a very moist environment
at the lower levels as indicated by CIRA LPW and GOES-16 water
vapor imagery. The wave is underneath a diffluent environment
between an elongated upper level low over Hispaniola and adjacent
waters and SW flow, which is supporting scattered showers and
tstms N of 13N between 61W and 74W.

A tropical wave is in the W Caribbean with axis S of 20N along
78W, moving W at 15 kt. CIRA LPW imagery shows shallow moisture
associated with the wave. However, strong deep layer wind shear
and a thin layer of Saharan dust hinder convection at the time.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from 16N16W to 12N26W to 09N36W. The
ITCZ begins W of a tropical wave near 07N38W and continues to
05N52W. Besides the convection mentioned in the tropical wave
section, heavy showers and tstms are from 07N-10N between 43W-
46W.

...DISCUSSION...

GULF OF MEXICO...

The Bermuda high extends a ridge axis SW across the Florida
Peninsula to the NW Gulf of Mexico providing light to locally
moderate SE to E winds. A surface trough is embedded over the W
Gulf from 26N90W to 23N96W. A tropical wave is also over the Bay
of Campeche. See above. CIRA LPW imagery shows shallow moisture
across the basin. Patches of scattered moderate convection are
over the W Gulf W of 88W. In the upper levels, the western half
of the Gulf is under a diffluent environment enhancing showers and
tstms W of 90W. Elsewhere, over the E gulf, upper level
diffluence supports showers from 23N-28N E of 86W. Expect
convection and showers over the western Gulf to continue through
Monday. Otherwise, surface ridging will prevail through early
next week.

CARIBBEAN SEA...

Two tropical waves are over the Caribbean Sea. See above.
Presently scattered showers are over the Leeward Islands. More
showers are along the coasts of Honduras and Nicaragua. GOES-16
RGBs indicates a thin layer of Saharan dust is over the basin.
This along with strong deep layer wind shear is suppressing
convection over the remainder of the Caribbean. Expect a strong
surface pressure gradient area N of Colombia to support fresh to
near gale force winds through Friday.

ATLANTIC OCEAN...

A non-tropical 1011 mb low centered over the central Atlantic
near 32N46W continues to produce limited shower activity.
Environmental conditions are expected to be only marginally
conducive for the low to acquire subtropical or tropical
characteristics while it moves little over the next day or so, and
then moves north-northeastward through Tuesday. A cold front
extends SW from the low along 30N45W to 37N50W to 25N60W to
27N73W. Scattered moderate convection is from 26N-29N between
44W-48W. Aside from the tropical waves, the remainder the Atlc is
under the influence of a surface ridges that supports fair
weather.

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

$$
MF/NR
This weather bulletin was brought to you by:
www.nashvilleweather.net