[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 121028
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
628 AM EDT Sat Aug 12 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 0600 UTC surface analysis and satellite imagery through
1030 UTC.

...SPECIAL FEATURES...

A 1012 mb low is centered near 23N68W. Scattered moderate
convection is noted from 20N-25N between 65W-70W. Dry air aloft
and unfavorable upper-level winds have limited significant
development during the past few days. Environmental conditions,
however, are expected to become a little more conducive for
development during the next day or two, and this system could
become a tropical depression over the weekend. The low is forecast
to move generally northwestward through the weekend and is likely
to turn northeastward away from the United States early next
week. There is a medium chance for tropical cyclone formation
during the next 48 hours.

...TROPICAL WAVES...

The axis of a tropical wave in the far eastern Atlantic is near
24W from 05N to 20N, moving W at 15-20 kt. Scattered moderate
convection is noted within 120 nm of the wave axis from 07N-12N.

The axis of a tropical wave in the central Atlantic is near 45W
from 05N to 19N, moving W at 15-20 kt. Scattered showers are
within 180 nm of the wave axis south of 10N.

The axis of a tropical wave in the central Caribbean is near 75W
from 05N to 20N. Scattered showers are noted over the southwest
Caribbean in the vicinity of this wave.


...ITCZ/MONSOON TROUGH...

The monsoon trough extends from the African coast near 18N16W to
13N23W to 11N37W to 08N46W. The Intertropical Convergence Zone
continues from 08N46W to the South American coast near 08N59W.
Aside from convection associated with the tropical waves,
scattered moderate convection is noted from 06N-11N between 26W-
32W.

...DISCUSSION...

GULF OF MEXICO...

A 1018 mb high is centered over the NE Gulf of Mexico near
26N88W. A thermal trough that developed over the Yucatan
Peninsula Friday evening is moving over the southwest Gulf
waters. Light to gentle anticyclonic flow is noted over the Gulf
waters, with the exception of moderate winds noted west of the
thermal trough moving off the Yucatan into the southwest Gulf.
High pressure will continue to remain centered over the Gulf
waters this weekend, with associated anticyclonic flow continuing.
A thermal trough will develop each evening over the Yucatan
Peninsula, shifting westward into the southwest Gulf during the
overnight hours, and dissipating over this area each morning.
Locally higher winds can be expected west of the trough axis.

CARIBBEAN SEA...

A tropical wave is moving through the central Caribbean. See
Tropical Waves section for details. The tropical wave will
continue to propagate westward, moving west of the area late
Sunday night. Fresh to locally strong winds prevail over the
south central Caribbean, while gentle to moderate winds prevail
elsewhere. These general conditions will prevail through the
weekend.

...HISPANIOLA...

Earlier active convection across the western half of Hispaniola
has dissipated. Expect diurnal convection to flare up each
afternoon over the weekend.

ATLANTIC OCEAN...

Please see the tropical wave section above for more on the
tropical waves moving across the Atlantic waters. Also, please see
above in the special features section for more on low pressure,
and the potential for tropical cyclogenesis, over the southwest
north Atlantic waters. Winds are generally in the light to
moderate range over the Atlantic waters, with the exception of
strong winds prevailing in the vicinity of the low pressure center
mentioned above. The subtropical high will strengthen over the
central Atlantic this weekend. The pressure gradient will tighten
between the area of high pressure and the tropical wave currently
over the eastern Atlantic this weekend. This will freshen winds
north of the tropical wave by Sunday as the wave propagates
westward.

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

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