[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 050515
TWDAT

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

...SPECIAL FEATURES...

Tropical Storm Leslie centered near 34.9N 57.6W at 05/0300 UTC
or 390 nm ENE of Bermuda moving N at 10 kt. Estimated minimum
central pressure is 984 mb. Maximum sustained wind speed is 55
kt with gusts to 65 kt. Scattered moderate convection is observed
north of 32N between 52W-67W. A northward motion with an increase
in forward speed overnight. A reduction in speed is forecast on
Friday and Friday night, with Leslie turning toward the east-
southeast over the weekend. Gradual weakening is forecast to
continue during the next several days. See the latest NHC
forecast/advisory under AWIPS/WMO headers MIATCPAT3/WTNT33 KNHC
for more details.

...TROPICAL WAVES...

A far eastern Atlantic tropical wave extends its axis along 31W
from 04N-17N, moving westward at 10-15 kt. Scattered moderate
convection is noted within 240 nm of the wave axis from 06N-14N.
GOES-16 Total Precipitable Water imagery shows a moisture maximum
surrounding the wave. The wave has an associated 700 mb trough, as
depicted by model analyses.

A central Atlantic tropical wave is along 49W from 06N-17N moving
westward around 10 kt. Scattered showers are occurring along the
wave axis and extending to 180 nm east of the wave axis from 08N-
10N. The wave has an associated 700 mb trough, as shown by model
analyses.

An eastern Caribbean tropical wave has its axis along 70W from
09N-19N, moving westward around 10 kt. The wave is becoming
diffuse as it gets closer to the gyre that has developed over the
central/west Caribbean. Scattered moderate convection is observed
in the vicinity of the wave enhanced by upper level diffluence
prevailing across the central Caribbean west of the wave.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Africa near 18N16W
to 10N22W to 08N38W. The ITCZ extends from 08N38W to 09N47W, then
continues west of a tropical wave from 09N51W to the coast of
northeast Venezuela near 09N61W. Aside from the convection
mentioned in the tropical waves section above, scattered showers
and thunderstorms are noted along and south of the monsoon trough
between 23W-29W and along the ITCZ between 50W-56W.

...DISCUSSION...

GULF OF MEXICO...

Scattered showers are moving westward over the eastern Gulf from
24N-27N between 83W-85W along a surface trough that extends along
83W. The remainder of the basin is under the influence of a
surface ridge, anchored by a pair of 1018 mb highs centered over
southeast CONUS.

Expect surface ridging to prevail over the forecast area through
the weekend. A surface trough will develop each evening over the
Yucatan Peninsula. The trough will move into the SW Gulf
overnight, where it will dissipate each morning. Moderate to fresh
winds will accompany the trough.

CARIBBEAN SEA...

A large cyclonic gyre, defined by a broad area of low pressure,
covers a portion of Central America and the western Caribbean Sea.
Within this gyre, a surface trough is analyzed from 20N81W to a
1006 mb low near 15N83W to 11N84W. Satellite imagery shows
scattered moderate to isolated strong convection across the
central Caribbean between 70W-83W. Some slow development of this
system is possible this weekend or early next week as the system
drifts northwestward across the northwestern Caribbean and the
southern Gulf of Mexico. A mid to upper level trough extending
over the Bahamas and Greater Antilles will help advect moisture
northwestward over the next several days. As a result, heavy
rainfall is likely to spread over portions of Hispaniola, Jamaica,
Cuba, the Yucatan Peninsula and Central America Friday through
early next week.

A tropical wave is over the eastern Caribbean. Refer to the
Tropical Waves section above for details. Large NNE swell
generated from Leslie will continue to pass through the Atlantic
passages into the Caribbean through the end of the week before
subsiding.

ATLANTIC OCEAN...

Two tropical waves are over the tropical Atlantic between the
west coast of Africa and the Lesser Antilles. See above for
details. Leslie is described in the Special Features section
above.

An E-W surface trough is analyzed to the east of Leslie from
31N29W to 27N41W. Scattered showers are seen south of this trough
from 25N-28N and east of 31W. Enhanced moisture from the tropical
wave along 49W is streaming northeastward between an upper-level
trough to the northwest and an upper-level ridge to the southeast.

Surface ridging prevails across the remainder of the basin.


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

$$

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