[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 130558
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
158 AM EDT Sat Oct 13 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...

Hurricane Leslie is centered near 35.5N 18.5W at 13/0600 UTC or
490 nm WSW of Lisbon, Portugal, or about 175 nm NNW of Madeira
Island moving ENE at 31 kt. Estimated minimum central pressure is
976 mb. Maximum sustained wind speed is 70 kt with gusts to 85
kt. A Tropical Storm Warning is in effect for Madeira Island. A
fast motion toward the east-northeast is expected to continue
through Sunday. On the forecast track, the center of Leslie will
pass north of Madeira Island this morning, approach the
southwestern portion of the Iberian Peninsula today, and move
inland over portions of Portugal and Spain tonight and Sunday.
Leslie is expected to transition into a hurricane-force post-
tropical cyclone later today. Weakening is forecast after Leslie
moves inland over the Iberian Peninsula tonight, and the post-
tropical cyclone is expected to dissipate by Monday. Numerous
moderate convection extends outward to 180 nm from the center in
the eastern semicircle and to 60 nm in the northwest quadrant.
See the latest NHC forecast/advisory under AWIPS/WMO headers
MIATCPAT3/WTNT33 KNHC for more details. Interests in Portugal and
Spain should monitor the progress of Leslie. Additional
information on this system can be found in products from the
Portuguese Institute for Sea and Atmosphere at www.ipma.pt.
Interests in Spain should refer to products from the State
Meteorological Agency at www.aemet.es.

Nadine has weakened to a tropical wave and the final advisory has
been issued. At 13/0300 UTC, the remnant of Nadine is near 16.0N
39.5W UTC or 880 nm W of the Southernmost Cabo Verde Islands
moving W at 15 kt. Estimated minimum central pressure is 1008 mb.
Maximum sustained wind speed is 30 kt with gusts to 40 kt. Nadine
will continue westward as a tropical wave, and redevelopment is
not expected. Scattered moderate convection is observed from 15N-
19N between 35W-38W. See the final NHC forecast/advisory under
AWIPS/WMO headers MIATCPAT5/WTNT35 KNHC for more details.

...TROPICAL WAVES...

The tropical wave that had previously been analyzed along 55W has
been repositioned along 54W from 07N-20N based on satellite
imagery and model diagnostics. Movement is westward at 5-10 kt. A
slight maximum in Total Precipitable Water is noted with the
wave. Scattered showers are noted from 10N-18N between the wave
axis and 48W. Isolated showers extend to 120 nm west of the wave
axis from 15N-18N.

A new tropical wave will likely be added to the 0600 UTC analysis.
The wave axis is approximately along 34/35W from 02N-11N moving
westward.

The remnants of Nadine will also be analyzed as a tropical wave on
the 0600 UTC map.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the eastern Atlantic from the coast of
Senegal near 14N17W and extends to 10N19W to 07N22W. The ITCZ
extends from 07N22W to 05N32W to 07N43W to 06N52W. Scattered
moderate convection is noted within 180 nm south of the ITCZ between
22W-28W. Scattered moderate and isolated strong convection is
seen within 210 nm north and 180 nm south of the ITCZ between
29W-37W.

GULF OF MEXICO...

A cold front extends across the basin from near Marco Island,
Florida to 23N88W to 23N91W, then becomes stationary at 23N91W to
to the coast of Mexico near 24N98W. No significant convection is
currently occurring with the front. Scattered showers and
thunderstorms cover the eastern Bay of Campeche from 19N-21N
between 90W-92W. Drier air is north of the front. The front is
currently weakening, and it will continue to weaken and wash out
as it drifts slowly southward through Saturday. High pressure
is now building in over the northern Gulf in the wake of the
front. Another cold front will move into the NW Gulf Mon night,
but will stall across the western Gulf through Wed night. Behind
the front, expect fresh to strong northerly winds and building
seas, with near gale force winds likely along the coasts of
Tamaulipas and Veracruz.

CARIBBEAN SEA...

An upper-level trough extends from 25N65W to Haiti to Jamaica. To
the southeast of this upper-trough, ample moisture is present
along with persistent shower and thunderstorm activity. These
showers and thunderstorms are affecting eastern portions of the
Dominican Republic, Puerto Rico and the Virgin Islands. Scattered
showers and thunderstorms extend across the eastern Caribbean from
the coast of Venezuela to Puerto Rico between 63W-70W.

A Central American Gyre has formed in the southwest Caribbean.
GOES-16 Total Precipitable water clear shows large scale rotation
associated with the gyre. A surface trough is analyzed through the
developing gyre from 18N79W to 13N80W. Scattered showers and
isolated thunderstorms are noted from 10N-18N between 70W-84W,
although little to no showers are occuring north of 15N and west
of 80W. This gyre, or broad low pressure area, will slowly shift
W toward central America through early next week. Enhanced showers
and thunderstorms are expected to persist over the southwest
Caribbean. Another surface trough is located from northwestern
Honduras to northern Belize. Scattered showers and thunderstorms
are over Belize, northern Guatemala and the Yucatan Peninsula.

To the south, the monsoon trough extends over the SW Caribbean Sea
from 12N73W to 12N80W to the coast of central Nicaragua. Scattered
moderate convection is occurring over Nicaragua and waters west of
81W and south of 14N.

NE swell from Hurricane Leslie will affect Caribbean passages
through tonight. Expect moderate trade winds to prevail across
the eastern Caribbean Sea through tonight. Mainly moderate to
fresh trades will prevail across the basin for the start of next
week. The tropical wave associated with the remnants of Nadine is
expected to reach the Lesser Antilles early next week.

ATLANTIC OCEAN...

Refer to the sections above for information on Hurricane Leslie,
the remnants of Nadine and the tropical wave along 54W.

A cold front extends across the west Atlantic from 32N72W to near
West Palm Beach, Florida. Isolated showers prevail well south and
east of the front to about 300 nm ahead of the front, and are
occurred near the northwest Bahamas and points northeast of the
Bahamas. A surface trough is analyzed north of Puerto Rico from
25N65W to 21N67W. The trough is helping to enhance showers and
thunderstorms over Puerto Rico and from Puerto Rico to 23N between
62W-69W.

Farther east, a cold front extends from 32N28W to 30N33W to
31N43W. A surface trough extends from 29N25W to 24N33W. Scattered
showers are from 27N-30N between 20W-34W.

A 1021 mb high is centered near 30N49W, leading to relatively
quiet weather from 25N-32N between 43W-53W.

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

$$
Hagen
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