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000
AXNT20 KNHC 132349
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
749 PM EDT Thu Jul 13 2017

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
2315 UTC.

...TROPICAL WAVES...

A tropical wave is in the E Atlc with axis extending from 15N31W
to 05N32W, moving W at 15-20 kt. The wave is in a region of
favorable wind shear, however extensive intrusion of Saharan dry
air and dust are hindering deep convection. Shallow moisture and
middle to upper level diffluence support scattered showers within
90 nm of the wave axis.

A tropical wave is in the W Atlc approaching the Windward Islands
with axis extending from 17N57W to 06N56W, moving W at 25 kt. The
wave is in a region of neutral to favorable wind shear. Saharan
dry air and dust reach 55W. Scattered moderate convection is from
11N-15N between 55W-60W.

A tropical wave is over the E Caribbean with axis extending from
22N68W to 11N68W, moving W at 15-20 kt. The wave is in a region
of favorable wind shear. Scattered moderate convection is over the
northern portion of the wave from 18N-22N between 66W-70W.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the coast of W Africa near 13N16W
to 10N30W to 06N40W. The ITCZ begins near 06N40W and continues to
08N55W. Besides the convection associated with the tropical waves,
scattered moderate convection is along the coast of W Africa from
10N-15N between 13W-18W. Isolated moderate convection is from
10N-12N between 23W-28W. Scattered moderate convection is from
04N-07N between 38W-49W.

...DISCUSSION...

...THE GULF OF MEXICO...

As of 2100 UTC, a surface trough is over the E Gulf of Mexico
from 29N85W to 22N82W. Scattered moderate convection is over the
the N Gulf N of 27N between 83W-95W to include the N Gulf States
from Louisiana to the Florida Panhandle. Widely scattered
moderate convection is over Florida and the Straits of Florida.
Scattered moderate to isolated strong convection is over W Cuba.
Elsewhere, 10 Kt SE surface flow is over the W Gulf with mostly
fair weather. In the upper levels, an upper level trough is over
the Gulf with axis along 88W. Expect over the next 24 hours for
additional convection to be over the N Central Gulf.

...THE CARIBBEAN SEA...

A tropical wave is moving across the E Caribbean. See above.
Scattered moderate to isolated strong convection is over the
Yucatan Peninsula from 19N-22N between 87W-90W. Similar convection
is over the SW Caribbean, Panama, Costa Rica, and SE Nicaragua,
from 07N-14N between 80W-84W. 10-20 kt tradewinds are elsewhere
with strongest winds along the coast of N Colombia. In the upper
levels, an upper level trough is over the W Caribbean. A small
upper level low is centered over Haiti near 19N73W. Expect the
E Caribbean tropical wave, together with another tropical wave
approaching the Windward Islands, to produce additional convection
over the next 24 hours. Also expect the convection over the SW
Caribbean to continue.

...HISPANIOLA...

Presently scattered moderate convection is over Hispaniola due to
an upper level low, and the E Caribbean tropical wave. Expect
convection to persist for the next 24 hours.

...THE ATLANTIC OCEAN...

Widely scattered moderate convection is over the N Bahamas due to
a surface trough. Scattered moderate convection is over the S
Bahamas due to the northern extent of a tropical wave. A very
large 1031 mb high is centered over the Central Atlantic near
35N46W. A Surface ridge axis extends SW from the high center to
Georgia producing fair weather. Of note in the upper levels, a
large upper level low is centered over the W Atlantic near 28N62W.
Scattered showers are within 240 nm radius of the center.

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

$$
Formosa