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Atlantic Tropical Weather Discussion



194 
AXNT20 KNHC 200529
TWDAT 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
129 AM EDT Fri Jul 20 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 0000 UTC surface analysis and satellite imagery through 
0515 UTC.

...TROPICAL WAVES...

A tropical wave is off the coast of west Africa along 20W from 
18N to 06N, moving W at 10-15 kt. Shallow moisture and upper 
level diffluence is supporting widely scattered moderate 
convection within 180 nm of the wave axis. The wave has Saharan 
dry air and dust further N and W of the wave axis. 

A tropical wave is in the central Atlantic with axis extending 
from 18N35W to 10N36W to 04N35W, moving W at 15 kt. The wave is 
moving across an extensive Saharan Air Layer Outbreak with dry air
and dust hindering convection.

A low amplitude tropical wave is over the central Atlantic with 
axis extending from 12N53W to 02N54W, moving W at 15 kt. 
Scattered moderate comvection is within 180 nm of the wave axis. 

A tropical wave is in the central Caribbean along 71W from 21N to
09N, moving W at 20 kt. The wave is in a strong deep layer wind 
shear environment. Scattered moderate convection is over
Hispaniola, N Colombia, and NW Venezuela. 

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends from W Africa near 16N16W to 
10N22W to 07N30W to 07N40W, where the ITCZ begins and continues 
to South America near 05N53W. Isolated moderate convection is 
from 06N to 10N between 24W and 30W, and from 04N to 08N between 
46W and 50W.

...DISCUSSION...

GULF OF MEXICO...

As of 20/0300 UTC, a 1012 mb low is centered over the Florida 
Panhandle near 30N87W. Widely scattered moderate convection is
over the NE Gulf of Mexico N of 26N and E of 92W to include
central and N Florida. This convection is being enhanced by upper
level diffluence to the S of an upper level trough centered N of 
Florida. A 1016 mb high is over the NW Gulf near 25N92W. 10 kt
anticyclonic surface winds are noted around this high. A surface
trough is inland over the Yucatan Peninsula. Widely scattered
moderate convection is over the Yucatan Peninsula and S Mexico.  
Expect the surface low to dissipate tonight, and a high pressure 
ridge to prevail over the Gulf along 25N through early next week.
A surface trough will also move off the Yucatan Peninsula into 
the Bay of Campeche each evening, accompanied by fresh nocturnal 
winds. 

CARIBBEAN SEA...

A tropical wave is over the central Caribbean. See above. Isolated
moderate convection is also along the S coast of Cuba. In the
upper levels, an upper level low is centered over SW Haiti near
18N74W enhancing convection. RGB imagery from GOES-16 shows a 
thin layer of Saharan Dust moving across the central and western 
portions of the basin. Expect the wave to traverse Hispaniola 
tonight and move to the W Caribbean Friday and Saturday, with
convection. More convection will prevail over the SW basin Sunday
primarily due to the eastern extent of the E Pacific monsoon 
trough. Fresh to strong winds are expected to continue over the 
central basin through the weekend. Near gale force winds will be 
likely, however, along the coast of Colombia this weekend.

ATLANTIC OCEAN...

A 1035 mb Azores High is centered near 41N37W. A surface ridge
axis extends SW to the W Atlantic near 28N70W. Widely scattered
moderate convection is over the W Atlantic N of 28N and W of 70W,
mostly due to upper level diffluence. Most of the central Atlantic
N of 20N between 35W-65W has fair weather. 

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

$$
Formosa