[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 061204 AAA
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
631 AM EDT TUE SEP 6 2016

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...

Post-tropical cyclone Hermine is centered near 39.6N 71.7W at
06/1200 UTC, or about 82 nm S of the eastern tip of Long Island.
Hermine is moving W at 5 knots. The estimated minimum central
pressure is 996 mb. Maximum sustained winds are 55 knots with
gusts to 65 knots. Scattered showers are within 390 nm from the
center to the NE and SW quadrants. A decrease in forward speed
is expected later today, and Hermine will likely become nearly
stationary by tonight. A turn toward the northeast is forecast
to occur on Wednesday. Hermine is expected to produce additional
light rainfall amounts not exceeding 1 inch along the mid-
Atlantic and southern New England coastline from New Jersey to
eastern Long Island to southeastern Massachusetts. Large waves
generated by Hermine will continue to affect the U.S. east coast
from the mid-Atlantic states through New England for another
couple of days. These waves are likely to cause life-threatening
surf and rip current conditions, and significant beach erosion.
Please read the latest NHC Intermediate Public Advisory under
AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC and the Forecast/Advisory
under the AWIPS/WMO headers MIATCMAT4/WTNT24 KNHC for more
details.

...TROPICAL WAVES...

A tropical wave came off the West African coast earlier this
morning. The wave extends from 06N to 18N with axis near 17W,
expected to move at 10 kt within the next 24 hours. The wave is in
a region of favorable deep layer wind shear and abundant low level
moisture that along with diffluent flow aloft support heavy
showers and tstms from 06N to 18N E of 20W.

A tropical wave is over the central Atlc extending from 07N to
20N with axis near 38W, moving W at 5-10 kt within the last 24
hours. The wave is in a region of favorable deep layer wind shear
and Saharan dry air and dust is not evident in its immediate
environment anymore. However, both CIRA LPW show the wave axis is
mainly in a dry environment, which is hindering convection and
any development at the time.

A tropical wave is over the central Caribbean Sea extending from
09N to 18N with axis near 70W, moving W at 20 kt within the last
24 hours. A 1010 mb center of low pressure is associated with the
wave, located near 15N70W and expected to dissipate in less than 24
hours. Abundant moisture in the vicinity of the wave and a
diffluent environment aloft support scattered heavy showers and
isolated tstms from 15N to 18N between 68W and 70W and isolated
showers elsewhere from 13N to 20N between 65W and 75W.

A tropical wave extends from the Bay of Campeche to southern
Mexico into the NE Pacific waters. The wave extends from 12N to
21N with axis near 94W, moving W at 15 kt within the last 24
hours. The wave is in a favorable deep layer wind shear
environment that along with abundant low level moisture support
scattered to isolated heavy showers and tstms across the W Bay of
Campeche.

...ITCZ/MONSOON TROUGH...

The Monsoon Trough extends across Africa into the east Tropical
Atlantic near 10N14W to 05N25W to 07N35W. The ITCZ begins near
08N49W to 09N55W to 10N62W. See the tropical waves section for
convection information. Otherwise, scattered moderate to isolated
strong convection is from 03N to 09N between 25W and 38W. Isolated
showers are within 60 nm either side of the ITCZ.

...DISCUSSION...

...THE GULF OF MEXICO...

Weak surface ridging prevails across the Gulf waters, except for
the far SW portion of the basin where a tropical wave along 94W
is supporting scattered to isolated heavy showers in the W Bay of
Campeche. Surface observations and scatterometer data indicate
moderate E to SE winds basin-wide, except for locally fresh E-NE
winds in the vicinity of the tropical wave axis. Cloudiness and
isolated showers over the SE basin are being supported by middle
to upper level diffluence. The tropical wave moving across the Bay
of Campeche over the next few days will support enhanced winds and
showers there. Elsewhere surface ridging will remain as the main
feature the next two days.

...THE CARIBBEAN SEA...

The main concern for the basin is a tropical wave that is moving
across the central Caribbean. Abundant moisture in the vicinity of the
wave and a diffluent environment aloft support scattered heavy
showers and isolated tstms from 15N to 18N between 68W and 70W and
isolated showers elsewhere from 13N to 20N between 65W and 75W. Locally
strong winds are possible in some of the heavier squalls passing
south of Dominican Republic. This disturbance could produce
periods of locally heavy rainfall and gusty winds over portions of
Hispaniola tonight and on Tuesday. Development of the wave is
unlikely while it moves westward across the Caribbean Sea for the
next few days. Upper-level winds could become a little more
conducive for development when the wave approaches the Yucatan
peninsula late this week. Please refer to the tropical waves
section for details.

...HISPANIOLA...

Increasing multilayered cloudiness has spread across the
Dominican Republic in advance of the tropical wave along 70W. The
potential for very heavy rainfall exists on Tue into Wed across
the island as the strong tropical wave continues westward in the
Caribbean. Drier weather is expected by Thursday as the wave moves
away from the island.

...THE ATLANTIC OCEAN...

Post-tropical cyclone Hermine is N of forecast waters. Please
refer to the special features section for details. A surface
trough, remnants of a frontal boundary, prevails across SW N
Atlantic waters extending from 30N70W to 26N77W to 23N82W.
Isolated showers and tstms are within 60 nm either side of the
trough axis. Farther east, a second surface trough extends from
29N52W to 23N56W, however no convection is associated with it a
the time. A third surface trough extends from 30N30W to 28N32W
with scattered showers within 60 nm either side of its axis N of
28N. Isolated showers are within 120 nm N of the Dominican
Republic and Puerto Rico coasts associated with a tropical wave in
the Caribbean with axis near 68W. Lastly, a 1012 mb low in the
deep tropics near 13N45W supports scattered showers from 07N to
15N between 40W and 47W. The remainder of the basin is dominated
by a broad but weak surface ridge.

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

$$
RAMOS/PAW
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