[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 190606
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
206 AM EDT FRI AUG 19 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 0000 UTC surface analysis and satellite imagery through
0545 UTC.

...SPECIAL FEATURES...
Tropical Storm Fiona is centered near 17.1N 41.8W at 19/0300 UTC
or about 1026 nm W of the Cape Verde Islands, moving NW at 7 kt.
Estimated minimum central pressure is 1006 mb. Maximum sustained
wind speed is 40 kt with gusts to 50 kt. A cluster of heavy
showers is from 16N-20N between 40W and 44W. See latest NHC
Forecast/Advisory under AWIPS/WMO headers MIATCMAT1/WTNT21 KNHC
for more details.

...TROPICAL WAVES...
Tropical wave extends from a 1009 mb low near 10N27W to 18N31W, moving
W at 15-20 kt within the last 24 hours. Saharan dry air and dust
engulf the wave, thus limiting the convection to the vicinity of
the monsoon trough W of the low pressure center. The convection is
numerous moderate to isolated strong from 07N-12N between 30W and
36W. Environmental conditions are expected to be conducive for
gradual development, and a tropical depression could form early
next week while the system moves westward across the tropical
Atlantic Ocean.

Tropical wave extends from 11N to 16N with axis near 57W, moving W
at 20 kt within the last 24 hours. Meteosat enhanced imagery and
LPW imagery from surface to 850 mb show there is dry air in the
wave environment. On the other hand, satellite derived data
indicate the wave is in a region of unfavorable deep layer wind
shear. Both the dry air and strong shear are hindering convection
at the time.

Tropical wave in the Caribbean extends from 11N-19N with axis near
73W, moving W at 20-25 kt within the last 24 hours. Shallow
moisture accompanies this wave that is in a region of mainly
neutral to unfavorable deep layer wind shear. These factors are
limiting the convection to isolated showers over Haiti and Western
Dominican Republic and northern adjacent waters.

...ITCZ/MONSOON TROUGH...
The Monsoon Trough extends from the African coast near 14N17W to
10N27W to 10N43W. The Intertropical Convergence Zone axis extends
from 10N43W to Guyana coastal waters near 07N57W. Aside from
convection associated with the tropical waves...isolated showers
are from 07N-13N E of 29W.

...DISCUSSION...

GULF OF MEXICO...
Surface ridging continues to extends from the Atlantic across
Florida and the Gulf waters N of 22N. In the Gulf, the ridge is
anchored by a 1019 mb high centered near 28N85W, which provides
gentle variable flow across the NE basin and E-SE gentle to
moderate flow elsewhere N of 22N. Over the Bay of Campeche, a
surface trough extends from 21N89W to 18N92W and supports moderate
to fresh NE flow within 90 nm off the Yucatan Peninsula coast. The
trough also supports isolated showers E of 94W and across the
Yucatan Peninsula. Dry air subsidence and unfavorable deep layer
wind shear support fair weather elsewhere. Mostly gentle to
moderate E-SE winds persist and are expected through the weekend
ahead.

CARIBBEAN SEA...
Water vapor imagery continue to show mostly dry air and stable
conditions basin-wide. The main feature in the Caribbean is a
tropical wave moving across the central basin supporting shower
activity over portions of Hispaniola and northern adjacent waters.
See the tropical waves sections for further details. The E pacific monsoon
trough support scattered showers in the SW basin S of 11N.
Isolated showers are in the Yucatan Channel and in the NW
basin waters W of 85W associated with a diffluence zone between
an elongated upper level low over the SE Gulf of Mexico and an
upper ridge over the W Caribbean. Otherwise...fresh to strong
trades prevail between 68W-80W. A new tropical wave is forecast
to enter the E Caribbean near sunrise today, however no
significant convection is expected to develop for the Lesser
Antilles.

...HISPANIOLA...
A tropical wave moving across the central Caribbean with axis
near 73W is accompanied with shallow moisture. The wave is also in a
region of mainly neutral to unfavorable deep layer wind shear. These
factors are limiting the convection to isolated showers over Haiti
and Western Dominican Republic and northern adjacent waters. This
shower activity is forecast to cease near sunrise time today.

ATLANTIC OCEAN...
The main feature in the basin is T.S. Fiona discussed in the
special features section. Over the SW North Atlc, an upper level
anticyclonic circulation centered near 21N65W is generating diffluent
flow on the northern periphery of the ridge to support heavy
showers and tstms from 23N-28N between 61W-66W. A weak surface
trough is analyzed from 30N73W to 25N78W supporting isolated
showers across the northern Bahamas. Otherwise...the remainder of
the SW North Atlc is under the influence of weak surface ridging.
Farther east...the central and eastern Atlc are influenced by a
surface ridge anchored by a 1021 mb high centered near 30N60W.

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

$$
RAMOS
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