[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 091759
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
159 PM EDT Wed Aug 9 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 1200 UTC surface analysis and satellite imagery through
1745 UTC.

...SPECIAL FEATURES...

Tropical Storm Franklin is centered near 20.2N 93.9W at 09/1500
UTC or about 125 nm NNE of Coatzacoalcos Mexico and about 145 nm
ENE of Veracruz Mexico moving W at 11 kt. Estimated minimum
central pressure is 985 mb. Maximum sustained wind speed is 60 kt
with gusts to 75 kt. Numerous strong convection is from 18N to
21.5N between 92W and 95W. Scattered moderate convection is
elsewhere from 16N to 25N between 90W and 98W. See the latest NHC
Intermediate Public Advisory under AWIPS/WMO headers
MIATCPAT2/WTNT32 KNHC and the full Forecast/Advisory under
AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details.

...TROPICAL WAVES...

A tropical wave is in the E Atlc with axis extending from 19N25W
to 07N29W, moving W at 10-15 kt. The wave is in a region of
mainly strong vertical wind shear and is experiencing extensive
Saharan dry air and dust intrusion to its environment, which is
hindering convection at the time.

A tropical wave is in the central Atlc associated with a 1012 mb
low near 17N55W. The wave axis extends from 23N52W to the low to
09N56W, and is moving W at 10 kt. The wave is in a region of
mainly low to moderate vertical wind shear. Shallow moisture along
with upper level diffluent flow support scattered moderate
convection from 16N to 25N between 49W and 55W. Environmental conditions
are forecast to become somewhat conducive for development of this
system late this week and this weekend while it move WNW over the
western Atlantic.

A tropical wave extends is in the W Caribbean with axis extending
from 22N79W 09N82W, moving W at 20-25 kt. The wave is in a region
of strong vertical wind shear and mainly shallow moisture. A
cluster of heavy showers and tstms is E of the wave axis between
Jamaica and Cuba being supported by diffluent flow embedded in a
broad upper level low centered just S of Jamaica. Scattered to
isolated heavy showers and tstms are S of 12N mainly associated
with the EPAC monsoon trough.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the African coast near 12N16W to
08N28W to 06N39W. The Intertropical Convergence Zone axis extends
from 06N39W to 06N48W to 08N51W. Aside from convection associated
with the tropical waves, a surface trough is analyzed from 16N45W
to 08N42W, which is supporting scattered moderate convection from
07N to 11N between 42W and 47W.

...DISCUSSION...

GULF OF MEXICO...

Tropical Storm Franklin continues to strenghen as it tracks W
across the SW Gulf waters. Numerous heavy showers are S of 21N
with isolated tstms noted just S of the storm center. Scattered
tstms are noted in Franklin's rainbands S of 24N. Franklin is
forecast to become a hurricane later today and reach the coast of
Mexico as a hurricane tonight or early Thursday. Rapid weakening
is expected after landfall in Mexico. For further information,
please see special features section. Isolated showers and tstms
are across SW Louisiana and adjacent coastal waters associated
with a 1013 mb low over SE Texas and the tail of a stationary
front extending SW to 27N97W. Fair weather and gentle to moderate
ESE winds reign elsewhere across the basin. A surface ridge will
build across the basin in the wake of the storm this upcoming
weekend.

CARIBBEAN SEA...

Isolated showers associated with the outer bands of Tropical
Storm Franklin are in the far NW Caribbean W of 85W. Farther east,
a tropical wave is along 81W, however lacking significant
convection. To the E of the wave, a cluster of heavy showers and
tstms is between Jamaica and Cuba being supported by diffluent
flow embedded in a broad upper level low centered just S of
Jamaica. Scattered showers and isolated tstms are S of 12N mainly
associated with the EPAC monsoon trough that extends from Costa
Rica to Panama to NW Colombia. In the SE basin, shallow moisture
and upper level diffluence support scattered to isolated showers S
of 13N E of 65W, including the Windward Islands. Water vapor
imagery show dry air across the remainder Caribbean, which
supports fair weather. Otherwise, fresh to strong winds continue
in the central basin between 70W and 76W continuing for the next
two days. Fresh to strong winds are also in the Gulf of Honduras
continuing through Friday morning. A tropical wave currently
along 55W will enter the E Caribbean waters Thursday morning.

...HISPANIOLA...

Clear skies prevail across the island being influenced by deep
layer dry air as indicated by the experimental GOES-16 imagery.
These conditions are forecast to continue through Friday when a
surface trough will move just N of the Island supporting isolated
showers.

ATLANTIC OCEAN...

A surface trough is moving across the central Bahamas supporting
scattered showers and isolated tstms from 22N to 27N between 73W
and 78W. Over the north-central waters, with lack of upper level
support, a stationary front continues to weaken along 30N40W to
28N50W to 28N58W. Isolated showers are within 120 nm either side
of the frontal boundary. A tropical wave in the central Atlc has
medium chances of development into a tropical cyclone over the
weekend as it moves over W Atlc waters. For further details on
tropical waves, see section above. Otherwise, a 1022 mb high is
centered near 27N38W, which is forecast to dissipate by Thu
morning.

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

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